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   * Copyright (c) 2012, 2015, Oracle and/or its affiliates. All rights reserved.
   * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   *
   * This code is free software; you can redistribute it and/or modify it
   * under the terms of the GNU General Public License version 2 only, as
   * published by the Free Software Foundation.  Oracle designates this
   * particular file as subject to the "Classpath" exception as provided
   * by Oracle in the LICENSE file that accompanied this code.
   *
   * This code is distributed in the hope that it will be useful, but WITHOUT
   * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
   * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
   * version 2 for more details (a copy is included in the LICENSE file that
   * accompanied this code).
   *
   * You should have received a copy of the GNU General Public License version
   * 2 along with this work; if not, write to the Free Software Foundation,
   * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
   *
   * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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   * questions.
   */
  
  /*
   * This file is available under and governed by the GNU General Public
   * License version 2 only, as published by the Free Software Foundation.
   * However, the following notice accompanied the original version of this
   * file:
   *
   * Copyright (c) 2008-2012, Stephen Colebourne & Michael Nascimento Santos
   *
   * All rights hg qreserved.
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions are met:
   *
   *  * Redistributions of source code must retain the above copyright notice,
   *    this list of conditions and the following disclaimer.
   *
   *  * Redistributions in binary form must reproduce the above copyright notice,
   *    this list of conditions and the following disclaimer in the documentation
   *    and/or other materials provided with the distribution.
   *
   *  * Neither the name of JSR-310 nor the names of its contributors
   *    may be used to endorse or promote products derived from this software
   *    without specific prior written permission.
   *
   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
   * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
   * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
   * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
   * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
   * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
   * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
   * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
   * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
   * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
   * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
   */
  package java.time.format;
  
  import android.icu.impl.ZoneMeta;
  import android.icu.text.LocaleDisplayNames;
  import android.icu.text.TimeZoneFormat;
  import android.icu.text.TimeZoneNames;
  import android.icu.util.Calendar;
  import android.icu.util.ULocale;
  
  import static java.time.temporal.ChronoField.DAY_OF_MONTH;
  import static java.time.temporal.ChronoField.HOUR_OF_DAY;
  import static java.time.temporal.ChronoField.INSTANT_SECONDS;
  import static java.time.temporal.ChronoField.MINUTE_OF_HOUR;
  import static java.time.temporal.ChronoField.MONTH_OF_YEAR;
  import static java.time.temporal.ChronoField.NANO_OF_SECOND;
  import static java.time.temporal.ChronoField.OFFSET_SECONDS;
  import static java.time.temporal.ChronoField.SECOND_OF_MINUTE;
  import static java.time.temporal.ChronoField.YEAR;
  
  import java.lang.ref.SoftReference;
  import java.math.BigDecimal;
  import java.math.BigInteger;
  import java.math.RoundingMode;
  import java.text.ParsePosition;
  import java.time.DateTimeException;
  import java.time.Instant;
  import java.time.LocalDate;
  import java.time.LocalDateTime;
  import java.time.ZoneId;
  import java.time.ZoneOffset;
  import java.time.chrono.ChronoLocalDate;
  import java.time.chrono.Chronology;
  import java.time.chrono.IsoChronology;
  import java.time.format.DateTimeTextProvider.LocaleStore;
  import java.time.temporal.ChronoField;
  import java.time.temporal.IsoFields;
  import java.time.temporal.TemporalAccessor;
  import java.time.temporal.TemporalField;
  import java.time.temporal.TemporalQueries;
  import java.time.temporal.TemporalQuery;
  import java.time.temporal.ValueRange;
  import java.time.temporal.WeekFields;
  import java.time.zone.ZoneRulesProvider;
  import java.util.AbstractMap.SimpleImmutableEntry;
  import java.util.ArrayList;
  import java.util.Collections;
  import java.util.Comparator;
  import java.util.HashMap;
  import java.util.HashSet;
  import java.util.Iterator;
  import java.util.LinkedHashMap;
  import java.util.List;
  import java.util.Locale;
  import java.util.Map;
  import java.util.Map.Entry;
  import java.util.Objects;
  import java.util.Set;
  import java.util.TimeZone;
  import java.util.concurrent.ConcurrentHashMap;
  import java.util.concurrent.ConcurrentMap;
  
  /**
   * Builder to create date-time formatters.
   * <p>
   * This allows a {@code DateTimeFormatter} to be created.
   * All date-time formatters are created ultimately using this builder.
   * <p>
   * The basic elements of date-time can all be added:
   * <ul>
   * <li>Value - a numeric value</li>
   * <li>Fraction - a fractional value including the decimal place. Always use this when
   * outputting fractions to ensure that the fraction is parsed correctly</li>
   * <li>Text - the textual equivalent for the value</li>
   * <li>OffsetId/Offset - the {@linkplain ZoneOffset zone offset}</li>
   * <li>ZoneId - the {@linkplain ZoneId time-zone} id</li>
   * <li>ZoneText - the name of the time-zone</li>
   * <li>ChronologyId - the {@linkplain Chronology chronology} id</li>
   * <li>ChronologyText - the name of the chronology</li>
   * <li>Literal - a text literal</li>
   * <li>Nested and Optional - formats can be nested or made optional</li>
   * </ul>
   * In addition, any of the elements may be decorated by padding, either with spaces or any other character.
   * <p>
   * Finally, a shorthand pattern, mostly compatible with {@code java.text.SimpleDateFormat SimpleDateFormat}
   * can be used, see {@link #appendPattern(String)}.
   * In practice, this simply parses the pattern and calls other methods on the builder.
   *
   * @implSpec
   * This class is a mutable builder intended for use from a single thread.
   *
   * @since 1.8
   */
  public final class DateTimeFormatterBuilder {
  
      /**
       * Query for a time-zone that is region-only.
       */
      private static final TemporalQuery<ZoneId> QUERY_REGION_ONLY = (temporal) -> {
          ZoneId zone = temporal.query(TemporalQueries.zoneId());
          return (zone != null && zone instanceof ZoneOffset == false ? zone : null);
      };
  
      /**
       * The currently active builder, used by the outermost builder.
       */
      private DateTimeFormatterBuilder active = this;
      /**
       * The parent builder, null for the outermost builder.
       */
      private final DateTimeFormatterBuilder parent;
      /**
       * The list of printers that will be used.
       */
      private final List<DateTimePrinterParser> printerParsers = new ArrayList<>();
      /**
       * Whether this builder produces an optional formatter.
       */
      private final boolean optional;
      /**
       * The width to pad the next field to.
       */
      private int padNextWidth;
      /**
       * The character to pad the next field with.
       */
      private char padNextChar;
      /**
       * The index of the last variable width value parser.
       */
      private int valueParserIndex = -1;
  
      /**
       * Gets the formatting pattern for date and time styles for a locale and chronology.
       * The locale and chronology are used to lookup the locale specific format
       * for the requested dateStyle and/or timeStyle.
       *
       * @param dateStyle  the FormatStyle for the date, null for time-only pattern
       * @param timeStyle  the FormatStyle for the time, null for date-only pattern
       * @param chrono  the Chronology, non-null
       * @param locale  the locale, non-null
       * @return the locale and Chronology specific formatting pattern
       * @throws IllegalArgumentException if both dateStyle and timeStyle are null
       */
      public static String getLocalizedDateTimePattern(FormatStyle dateStyle, FormatStyle timeStyle,
              Chronology chrono, Locale locale) {
          Objects.requireNonNull(locale, "locale");
          Objects.requireNonNull(chrono, "chrono");
          if (dateStyle == null && timeStyle == null) {
              throw new IllegalArgumentException("Either dateStyle or timeStyle must be non-null");
          }
  
          // Android-changed: get format string from ICU.
          // LocaleResources lr = LocaleProviderAdapter.getResourceBundleBased()
          //         .getLocaleResources(locale);
          // String pattern = lr.getJavaTimeDateTimePattern(
          //         convertStyle(timeStyle), convertStyle(dateStyle), chrono.getCalendarType());
          String pattern = Calendar.getDateTimeFormatString(
                  ULocale.forLocale(locale), chrono.getCalendarType(),
                  convertStyle(dateStyle), convertStyle(timeStyle));
          return pattern;
      }
  
      /**
       * Converts the given FormatStyle to the java.text.DateFormat style.
       *
       * @param style  the FormatStyle style
       * @return the int style, or -1 if style is null, indicating un-required
       */
      private static int convertStyle(FormatStyle style) {
          if (style == null) {
              return -1;
          }
          return style.ordinal();  // indices happen to align
      }
  
      /**
       * Constructs a new instance of the builder.
       */
      public DateTimeFormatterBuilder() {
          super();
          parent = null;
          optional = false;
      }
  
      /**
       * Constructs a new instance of the builder.
       *
       * @param parent  the parent builder, not null
       * @param optional  whether the formatter is optional, not null
       */
      private DateTimeFormatterBuilder(DateTimeFormatterBuilder parent, boolean optional) {
          super();
          this.parent = parent;
          this.optional = optional;
      }
  
      //-----------------------------------------------------------------------
      /**
       * Changes the parse style to be case sensitive for the remainder of the formatter.
       * <p>
       * Parsing can be case sensitive or insensitive - by default it is case sensitive.
       * This method allows the case sensitivity setting of parsing to be changed.
       * <p>
       * Calling this method changes the state of the builder such that all
       * subsequent builder method calls will parse text in case sensitive mode.
       * See {@link #parseCaseInsensitive} for the opposite setting.
       * The parse case sensitive/insensitive methods may be called at any point
       * in the builder, thus the parser can swap between case parsing modes
       * multiple times during the parse.
       * <p>
       * Since the default is case sensitive, this method should only be used after
       * a previous call to {@code #parseCaseInsensitive}.
       *
       * @return this, for chaining, not null
       */
      public DateTimeFormatterBuilder parseCaseSensitive() {
          appendInternal(SettingsParser.SENSITIVE);
          return this;
      }
  
      /**
       * Changes the parse style to be case insensitive for the remainder of the formatter.
       * <p>
       * Parsing can be case sensitive or insensitive - by default it is case sensitive.
       * This method allows the case sensitivity setting of parsing to be changed.
       * <p>
       * Calling this method changes the state of the builder such that all
       * subsequent builder method calls will parse text in case insensitive mode.
       * See {@link #parseCaseSensitive()} for the opposite setting.
       * The parse case sensitive/insensitive methods may be called at any point
       * in the builder, thus the parser can swap between case parsing modes
       * multiple times during the parse.
       *
       * @return this, for chaining, not null
       */
      public DateTimeFormatterBuilder parseCaseInsensitive() {
          appendInternal(SettingsParser.INSENSITIVE);
          return this;
      }
  
      //-----------------------------------------------------------------------
      /**
       * Changes the parse style to be strict for the remainder of the formatter.
       * <p>
       * Parsing can be strict or lenient - by default its strict.
       * This controls the degree of flexibility in matching the text and sign styles.
       * <p>
       * When used, this method changes the parsing to be strict from this point onwards.
       * As strict is the default, this is normally only needed after calling {@link #parseLenient()}.
       * The change will remain in force until the end of the formatter that is eventually
       * constructed or until {@code parseLenient} is called.
       *
       * @return this, for chaining, not null
       */
      public DateTimeFormatterBuilder parseStrict() {
          appendInternal(SettingsParser.STRICT);
          return this;
      }
  
      /**
       * Changes the parse style to be lenient for the remainder of the formatter.
       * Note that case sensitivity is set separately to this method.
       * <p>
       * Parsing can be strict or lenient - by default its strict.
       * This controls the degree of flexibility in matching the text and sign styles.
       * Applications calling this method should typically also call {@link #parseCaseInsensitive()}.
       * <p>
       * When used, this method changes the parsing to be lenient from this point onwards.
       * The change will remain in force until the end of the formatter that is eventually
       * constructed or until {@code parseStrict} is called.
       *
       * @return this, for chaining, not null
       */
      public DateTimeFormatterBuilder parseLenient() {
          appendInternal(SettingsParser.LENIENT);
          return this;
      }
  
      //-----------------------------------------------------------------------
      /**
       * Appends a default value for a field to the formatter for use in parsing.
       * <p>
       * This appends an instruction to the builder to inject a default value
       * into the parsed result. This is especially useful in conjunction with
       * optional parts of the formatter.
       * <p>
       * For example, consider a formatter that parses the year, followed by
       * an optional month, with a further optional day-of-month. Using such a
       * formatter would require the calling code to check whether a full date,
       * year-month or just a year had been parsed. This method can be used to
       * default the month and day-of-month to a sensible value, such as the
       * first of the month, allowing the calling code to always get a date.
       * <p>
       * During formatting, this method has no effect.
       * <p>
       * During parsing, the current state of the parse is inspected.
       * If the specified field has no associated value, because it has not been
       * parsed successfully at that point, then the specified value is injected
       * into the parse result. Injection is immediate, thus the field-value pair
       * will be visible to any subsequent elements in the formatter.
       * As such, this method is normally called at the end of the builder.
       *
       * @param field  the field to default the value of, not null
       * @param value  the value to default the field to
       * @return this, for chaining, not null
       */
      public DateTimeFormatterBuilder parseDefaulting(TemporalField field, long value) {
          Objects.requireNonNull(field, "field");
          appendInternal(new DefaultValueParser(field, value));
          return this;
      }
  
      //-----------------------------------------------------------------------
      /**
       * Appends the value of a date-time field to the formatter using a normal
       * output style.
       * <p>
       * The value of the field will be output during a format.
       * If the value cannot be obtained then an exception will be thrown.
       * <p>
       * The value will be printed as per the normal format of an integer value.
       * Only negative numbers will be signed. No padding will be added.
       * <p>
       * The parser for a variable width value such as this normally behaves greedily,
       * requiring one digit, but accepting as many digits as possible.
       * This behavior can be affected by 'adjacent value parsing'.
       * See {@link #appendValue(TemporalField, int)} for full details.
       *
       * @param field  the field to append, not null
       * @return this, for chaining, not null
       */
      public DateTimeFormatterBuilder appendValue(TemporalField field) {
          Objects.requireNonNull(field, "field");
          appendValue(new NumberPrinterParser(field, 1, 19, SignStyle.NORMAL));
          return this;
      }
  
      /**
       * Appends the value of a date-time field to the formatter using a fixed
       * width, zero-padded approach.
       * <p>
       * The value of the field will be output during a format.
       * If the value cannot be obtained then an exception will be thrown.
       * <p>
       * The value will be zero-padded on the left. If the size of the value
       * means that it cannot be printed within the width then an exception is thrown.
       * If the value of the field is negative then an exception is thrown during formatting.
       * <p>
       * This method supports a special technique of parsing known as 'adjacent value parsing'.
       * This technique solves the problem where a value, variable or fixed width, is followed by one or more
       * fixed length values. The standard parser is greedy, and thus it would normally
       * steal the digits that are needed by the fixed width value parsers that follow the
       * variable width one.
       * <p>
       * No action is required to initiate 'adjacent value parsing'.
       * When a call to {@code appendValue} is made, the builder
       * enters adjacent value parsing setup mode. If the immediately subsequent method
       * call or calls on the same builder are for a fixed width value, then the parser will reserve
       * space so that the fixed width values can be parsed.
       * <p>
       * For example, consider {@code builder.appendValue(YEAR).appendValue(MONTH_OF_YEAR, 2);}
       * The year is a variable width parse of between 1 and 19 digits.
       * The month is a fixed width parse of 2 digits.
       * Because these were appended to the same builder immediately after one another,
       * the year parser will reserve two digits for the month to parse.
       * Thus, the text '201106' will correctly parse to a year of 2011 and a month of 6.
       * Without adjacent value parsing, the year would greedily parse all six digits and leave
       * nothing for the month.
       * <p>
       * Adjacent value parsing applies to each set of fixed width not-negative values in the parser
       * that immediately follow any kind of value, variable or fixed width.
       * Calling any other append method will end the setup of adjacent value parsing.
       * Thus, in the unlikely event that you need to avoid adjacent value parsing behavior,
       * simply add the {@code appendValue} to another {@code DateTimeFormatterBuilder}
       * and add that to this builder.
       * <p>
       * If adjacent parsing is active, then parsing must match exactly the specified
       * number of digits in both strict and lenient modes.
       * In addition, no positive or negative sign is permitted.
       *
       * @param field  the field to append, not null
       * @param width  the width of the printed field, from 1 to 19
       * @return this, for chaining, not null
       * @throws IllegalArgumentException if the width is invalid
       */
      public DateTimeFormatterBuilder appendValue(TemporalField field, int width) {
          Objects.requireNonNull(field, "field");
          if (width < 1 || width > 19) {
              throw new IllegalArgumentException("The width must be from 1 to 19 inclusive but was " + width);
          }
          NumberPrinterParser pp = new NumberPrinterParser(field, width, width, SignStyle.NOT_NEGATIVE);
          appendValue(pp);
          return this;
      }
  
      /**
       * Appends the value of a date-time field to the formatter providing full
       * control over formatting.
       * <p>
       * The value of the field will be output during a format.
       * If the value cannot be obtained then an exception will be thrown.
       * <p>
       * This method provides full control of the numeric formatting, including
       * zero-padding and the positive/negative sign.
       * <p>
       * The parser for a variable width value such as this normally behaves greedily,
       * accepting as many digits as possible.
       * This behavior can be affected by 'adjacent value parsing'.
       * See {@link #appendValue(TemporalField, int)} for full details.
       * <p>
       * In strict parsing mode, the minimum number of parsed digits is {@code minWidth}
       * and the maximum is {@code maxWidth}.
       * In lenient parsing mode, the minimum number of parsed digits is one
       * and the maximum is 19 (except as limited by adjacent value parsing).
       * <p>
       * If this method is invoked with equal minimum and maximum widths and a sign style of
       * {@code NOT_NEGATIVE} then it delegates to {@code appendValue(TemporalField,int)}.
       * In this scenario, the formatting and parsing behavior described there occur.
       *
       * @param field  the field to append, not null
       * @param minWidth  the minimum field width of the printed field, from 1 to 19
       * @param maxWidth  the maximum field width of the printed field, from 1 to 19
       * @param signStyle  the positive/negative output style, not null
       * @return this, for chaining, not null
       * @throws IllegalArgumentException if the widths are invalid
       */
      public DateTimeFormatterBuilder appendValue(
              TemporalField field, int minWidth, int maxWidth, SignStyle signStyle) {
          if (minWidth == maxWidth && signStyle == SignStyle.NOT_NEGATIVE) {
              return appendValue(field, maxWidth);
          }
          Objects.requireNonNull(field, "field");
          Objects.requireNonNull(signStyle, "signStyle");
          if (minWidth < 1 || minWidth > 19) {
              throw new IllegalArgumentException("The minimum width must be from 1 to 19 inclusive but was " + minWidth);
          }
          if (maxWidth < 1 || maxWidth > 19) {
              throw new IllegalArgumentException("The maximum width must be from 1 to 19 inclusive but was " + maxWidth);
          }
          if (maxWidth < minWidth) {
              throw new IllegalArgumentException("The maximum width must exceed or equal the minimum width but " +
                      maxWidth + " < " + minWidth);
          }
          NumberPrinterParser pp = new NumberPrinterParser(field, minWidth, maxWidth, signStyle);
          appendValue(pp);
          return this;
      }
  
      //-----------------------------------------------------------------------
      /**
       * Appends the reduced value of a date-time field to the formatter.
       * <p>
       * Since fields such as year vary by chronology, it is recommended to use the
       * {@link #appendValueReduced(TemporalField, int, int, ChronoLocalDate)} date}
       * variant of this method in most cases. This variant is suitable for
       * simple fields or working with only the ISO chronology.
       * <p>
       * For formatting, the {@code width} and {@code maxWidth} are used to
       * determine the number of characters to format.
       * If they are equal then the format is fixed width.
       * If the value of the field is within the range of the {@code baseValue} using
       * {@code width} characters then the reduced value is formatted otherwise the value is
       * truncated to fit {@code maxWidth}.
       * The rightmost characters are output to match the width, left padding with zero.
       * <p>
       * For strict parsing, the number of characters allowed by {@code width} to {@code maxWidth} are parsed.
       * For lenient parsing, the number of characters must be at least 1 and less than 10.
       * If the number of digits parsed is equal to {@code width} and the value is positive,
       * the value of the field is computed to be the first number greater than
       * or equal to the {@code baseValue} with the same least significant characters,
       * otherwise the value parsed is the field value.
       * This allows a reduced value to be entered for values in range of the baseValue
       * and width and absolute values can be entered for values outside the range.
       * <p>
       * For example, a base value of {@code 1980} and a width of {@code 2} will have
       * valid values from {@code 1980} to {@code 2079}.
       * During parsing, the text {@code "12"} will result in the value {@code 2012} as that
       * is the value within the range where the last two characters are "12".
       * By contrast, parsing the text {@code "1915"} will result in the value {@code 1915}.
       *
       * @param field  the field to append, not null
       * @param width  the field width of the printed and parsed field, from 1 to 10
       * @param maxWidth  the maximum field width of the printed field, from 1 to 10
       * @param baseValue  the base value of the range of valid values
       * @return this, for chaining, not null
       * @throws IllegalArgumentException if the width or base value is invalid
       */
      public DateTimeFormatterBuilder appendValueReduced(TemporalField field,
              int width, int maxWidth, int baseValue) {
          Objects.requireNonNull(field, "field");
          ReducedPrinterParser pp = new ReducedPrinterParser(field, width, maxWidth, baseValue, null);
          appendValue(pp);
          return this;
      }
  
      /**
       * Appends the reduced value of a date-time field to the formatter.
       * <p>
       * This is typically used for formatting and parsing a two digit year.
       * <p>
       * The base date is used to calculate the full value during parsing.
       * For example, if the base date is 1950-01-01 then parsed values for
       * a two digit year parse will be in the range 1950-01-01 to 2049-12-31.
       * Only the year would be extracted from the date, thus a base date of
       * 1950-08-25 would also parse to the range 1950-01-01 to 2049-12-31.
       * This behavior is necessary to support fields such as week-based-year
       * or other calendar systems where the parsed value does not align with
       * standard ISO years.
       * <p>
       * The exact behavior is as follows. Parse the full set of fields and
       * determine the effective chronology using the last chronology if
       * it appears more than once. Then convert the base date to the
       * effective chronology. Then extract the specified field from the
       * chronology-specific base date and use it to determine the
       * {@code baseValue} used below.
       * <p>
       * For formatting, the {@code width} and {@code maxWidth} are used to
       * determine the number of characters to format.
       * If they are equal then the format is fixed width.
       * If the value of the field is within the range of the {@code baseValue} using
       * {@code width} characters then the reduced value is formatted otherwise the value is
       * truncated to fit {@code maxWidth}.
       * The rightmost characters are output to match the width, left padding with zero.
       * <p>
       * For strict parsing, the number of characters allowed by {@code width} to {@code maxWidth} are parsed.
       * For lenient parsing, the number of characters must be at least 1 and less than 10.
       * If the number of digits parsed is equal to {@code width} and the value is positive,
       * the value of the field is computed to be the first number greater than
       * or equal to the {@code baseValue} with the same least significant characters,
       * otherwise the value parsed is the field value.
       * This allows a reduced value to be entered for values in range of the baseValue
       * and width and absolute values can be entered for values outside the range.
       * <p>
       * For example, a base value of {@code 1980} and a width of {@code 2} will have
       * valid values from {@code 1980} to {@code 2079}.
       * During parsing, the text {@code "12"} will result in the value {@code 2012} as that
       * is the value within the range where the last two characters are "12".
       * By contrast, parsing the text {@code "1915"} will result in the value {@code 1915}.
       *
       * @param field  the field to append, not null
       * @param width  the field width of the printed and parsed field, from 1 to 10
       * @param maxWidth  the maximum field width of the printed field, from 1 to 10
       * @param baseDate  the base date used to calculate the base value for the range
       *  of valid values in the parsed chronology, not null
       * @return this, for chaining, not null
       * @throws IllegalArgumentException if the width or base value is invalid
       */
      public DateTimeFormatterBuilder appendValueReduced(
              TemporalField field, int width, int maxWidth, ChronoLocalDate baseDate) {
          Objects.requireNonNull(field, "field");
          Objects.requireNonNull(baseDate, "baseDate");
          ReducedPrinterParser pp = new ReducedPrinterParser(field, width, maxWidth, 0, baseDate);
          appendValue(pp);
          return this;
      }
  
      /**
       * Appends a fixed or variable width printer-parser handling adjacent value mode.
       * If a PrinterParser is not active then the new PrinterParser becomes
       * the active PrinterParser.
       * Otherwise, the active PrinterParser is modified depending on the new PrinterParser.
       * If the new PrinterParser is fixed width and has sign style {@code NOT_NEGATIVE}
       * then its width is added to the active PP and
       * the new PrinterParser is forced to be fixed width.
       * If the new PrinterParser is variable width, the active PrinterParser is changed
       * to be fixed width and the new PrinterParser becomes the active PP.
       *
       * @param pp  the printer-parser, not null
       * @return this, for chaining, not null
       */
      private DateTimeFormatterBuilder appendValue(NumberPrinterParser pp) {
          if (active.valueParserIndex >= 0) {
              final int activeValueParser = active.valueParserIndex;
  
              // adjacent parsing mode, update setting in previous parsers
              NumberPrinterParser basePP = (NumberPrinterParser) active.printerParsers.get(activeValueParser);
              if (pp.minWidth == pp.maxWidth && pp.signStyle == SignStyle.NOT_NEGATIVE) {
                  // Append the width to the subsequentWidth of the active parser
                  basePP = basePP.withSubsequentWidth(pp.maxWidth);
                  // Append the new parser as a fixed width
                  appendInternal(pp.withFixedWidth());
                  // Retain the previous active parser
                  active.valueParserIndex = activeValueParser;
              } else {
                  // Modify the active parser to be fixed width
                  basePP = basePP.withFixedWidth();
                  // The new parser becomes the mew active parser
                  active.valueParserIndex = appendInternal(pp);
              }
              // Replace the modified parser with the updated one
              active.printerParsers.set(activeValueParser, basePP);
          } else {
              // The new Parser becomes the active parser
              active.valueParserIndex = appendInternal(pp);
          }
          return this;
      }
  
      //-----------------------------------------------------------------------
      /**
       * Appends the fractional value of a date-time field to the formatter.
       * <p>
       * The fractional value of the field will be output including the
       * preceding decimal point. The preceding value is not output.
       * For example, the second-of-minute value of 15 would be output as {@code .25}.
       * <p>
       * The width of the printed fraction can be controlled. Setting the
       * minimum width to zero will cause no output to be generated.
       * The printed fraction will have the minimum width necessary between
       * the minimum and maximum widths - trailing zeroes are omitted.
       * No rounding occurs due to the maximum width - digits are simply dropped.
       * <p>
       * When parsing in strict mode, the number of parsed digits must be between
       * the minimum and maximum width. When parsing in lenient mode, the minimum
       * width is considered to be zero and the maximum is nine.
       * <p>
       * If the value cannot be obtained then an exception will be thrown.
       * If the value is negative an exception will be thrown.
       * If the field does not have a fixed set of valid values then an
       * exception will be thrown.
       * If the field value in the date-time to be printed is invalid it
       * cannot be printed and an exception will be thrown.
       *
       * @param field  the field to append, not null
       * @param minWidth  the minimum width of the field excluding the decimal point, from 0 to 9
       * @param maxWidth  the maximum width of the field excluding the decimal point, from 1 to 9
       * @param decimalPoint  whether to output the localized decimal point symbol
       * @return this, for chaining, not null
       * @throws IllegalArgumentException if the field has a variable set of valid values or
       *  either width is invalid
       */
      public DateTimeFormatterBuilder appendFraction(
              TemporalField field, int minWidth, int maxWidth, boolean decimalPoint) {
          appendInternal(new FractionPrinterParser(field, minWidth, maxWidth, decimalPoint));
          return this;
      }
  
      //-----------------------------------------------------------------------
      /**
       * Appends the text of a date-time field to the formatter using the full
       * text style.
       * <p>
       * The text of the field will be output during a format.
       * The value must be within the valid range of the field.
       * If the value cannot be obtained then an exception will be thrown.
       * If the field has no textual representation, then the numeric value will be used.
       * <p>
       * The value will be printed as per the normal format of an integer value.
       * Only negative numbers will be signed. No padding will be added.
       *
       * @param field  the field to append, not null
       * @return this, for chaining, not null
       */
      public DateTimeFormatterBuilder appendText(TemporalField field) {
          return appendText(field, TextStyle.FULL);
      }
  
      /**
       * Appends the text of a date-time field to the formatter.
       * <p>
       * The text of the field will be output during a format.
       * The value must be within the valid range of the field.
       * If the value cannot be obtained then an exception will be thrown.
       * If the field has no textual representation, then the numeric value will be used.
       * <p>
       * The value will be printed as per the normal format of an integer value.
       * Only negative numbers will be signed. No padding will be added.
       *
       * @param field  the field to append, not null
       * @param textStyle  the text style to use, not null
       * @return this, for chaining, not null
       */
      public DateTimeFormatterBuilder appendText(TemporalField field, TextStyle textStyle) {
          Objects.requireNonNull(field, "field");
          Objects.requireNonNull(textStyle, "textStyle");
          appendInternal(new TextPrinterParser(field, textStyle, DateTimeTextProvider.getInstance()));
          return this;
      }
  
      /**
       * Appends the text of a date-time field to the formatter using the specified
       * map to supply the text.
       * <p>
       * The standard text outputting methods use the localized text in the JDK.
       * This method allows that text to be specified directly.
       * The supplied map is not validated by the builder to ensure that formatting or
       * parsing is possible, thus an invalid map may throw an error during later use.
       * <p>
       * Supplying the map of text provides considerable flexibility in formatting and parsing.
       * For example, a legacy application might require or supply the months of the
       * year as "JNY", "FBY", "MCH" etc. These do not match the standard set of text
       * for localized month names. Using this method, a map can be created which
       * defines the connection between each value and the text:
       * <pre>
       * Map&lt;Long, String&gt; map = new HashMap&lt;&gt;();
       * map.put(1L, "JNY");
       * map.put(2L, "FBY");
       * map.put(3L, "MCH");
       * ...
       * builder.appendText(MONTH_OF_YEAR, map);
       * </pre>
       * <p>
       * Other uses might be to output the value with a suffix, such as "1st", "2nd", "3rd",
       * or as Roman numerals "I", "II", "III", "IV".
       * <p>
       * During formatting, the value is obtained and checked that it is in the valid range.
       * If text is not available for the value then it is output as a number.
       * During parsing, the parser will match against the map of text and numeric values.
       *
       * @param field  the field to append, not null
       * @param textLookup  the map from the value to the text
       * @return this, for chaining, not null
       */
      public DateTimeFormatterBuilder appendText(TemporalField field, Map<Long, String> textLookup) {
          Objects.requireNonNull(field, "field");
          Objects.requireNonNull(textLookup, "textLookup");
          Map<Long, String> copy = new LinkedHashMap<>(textLookup);
          Map<TextStyle, Map<Long, String>> map = Collections.singletonMap(TextStyle.FULL, copy);
          final LocaleStore store = new LocaleStore(map);
          DateTimeTextProvider provider = new DateTimeTextProvider() {
              @Override
              public String getText(TemporalField field, long value, TextStyle style, Locale locale) {
                  return store.getText(value, style);
              }
              @Override
              public Iterator<Entry<String, Long>> getTextIterator(TemporalField field, TextStyle style, Locale locale) {
                  return store.getTextIterator(style);
              }
          };
          appendInternal(new TextPrinterParser(field, TextStyle.FULL, provider));
          return this;
      }
  
      //-----------------------------------------------------------------------
      /**
       * Appends an instant using ISO-8601 to the formatter, formatting fractional
       * digits in groups of three.
       * <p>
       * Instants have a fixed output format.
       * They are converted to a date-time with a zone-offset of UTC and formatted
       * using the standard ISO-8601 format.
       * With this method, formatting nano-of-second outputs zero, three, six
       * or nine digits digits as necessary.
       * The localized decimal style is not used.
       * <p>
       * The instant is obtained using {@link ChronoField#INSTANT_SECONDS INSTANT_SECONDS}
       * and optionally (@code NANO_OF_SECOND). The value of {@code INSTANT_SECONDS}
       * may be outside the maximum range of {@code LocalDateTime}.
       * <p>
       * The {@linkplain ResolverStyle resolver style} has no effect on instant parsing.
       * The end-of-day time of '24:00' is handled as midnight at the start of the following day.
       * The leap-second time of '23:59:59' is handled to some degree, see
       * {@link DateTimeFormatter#parsedLeapSecond()} for full details.
       * <p>
       * An alternative to this method is to format/parse the instant as a single
       * epoch-seconds value. That is achieved using {@code appendValue(INSTANT_SECONDS)}.
       *
       * @return this, for chaining, not null
       */
      public DateTimeFormatterBuilder appendInstant() {
          appendInternal(new InstantPrinterParser(-2));
          return this;
      }
  
      /**
       * Appends an instant using ISO-8601 to the formatter with control over
       * the number of fractional digits.
       * <p>
       * Instants have a fixed output format, although this method provides some
       * control over the fractional digits. They are converted to a date-time
       * with a zone-offset of UTC and printed using the standard ISO-8601 format.
       * The localized decimal style is not used.
       * <p>
       * The {@code fractionalDigits} parameter allows the output of the fractional
       * second to be controlled. Specifying zero will cause no fractional digits
       * to be output. From 1 to 9 will output an increasing number of digits, using
       * zero right-padding if necessary. The special value -1 is used to output as
       * many digits as necessary to avoid any trailing zeroes.
       * <p>
       * When parsing in strict mode, the number of parsed digits must match the
       * fractional digits. When parsing in lenient mode, any number of fractional
       * digits from zero to nine are accepted.
       * <p>
       * The instant is obtained using {@link ChronoField#INSTANT_SECONDS INSTANT_SECONDS}
       * and optionally (@code NANO_OF_SECOND). The value of {@code INSTANT_SECONDS}
       * may be outside the maximum range of {@code LocalDateTime}.
       * <p>
       * The {@linkplain ResolverStyle resolver style} has no effect on instant parsing.
       * The end-of-day time of '24:00' is handled as midnight at the start of the following day.
       * The leap-second time of '23:59:60' is handled to some degree, see
       * {@link DateTimeFormatter#parsedLeapSecond()} for full details.
       * <p>
       * An alternative to this method is to format/parse the instant as a single
       * epoch-seconds value. That is achieved using {@code appendValue(INSTANT_SECONDS)}.
       *
       * @param fractionalDigits  the number of fractional second digits to format with,
       *  from 0 to 9, or -1 to use as many digits as necessary
       * @return this, for chaining, not null
       */
      public DateTimeFormatterBuilder appendInstant(int fractionalDigits) {
          if (fractionalDigits < -1 || fractionalDigits > 9) {
              throw new IllegalArgumentException("The fractional digits must be from -1 to 9 inclusive but was " + fractionalDigits);
          }
          appendInternal(new InstantPrinterParser(fractionalDigits));
          return this;
      }
  
      //-----------------------------------------------------------------------
      /**
       * Appends the zone offset, such as '+01:00', to the formatter.
       * <p>
       * This appends an instruction to format/parse the offset ID to the builder.
       * This is equivalent to calling {@code appendOffset("+HH:MM:ss", "Z")}.
       *
       * @return this, for chaining, not null
       */
      public DateTimeFormatterBuilder appendOffsetId() {
          appendInternal(OffsetIdPrinterParser.INSTANCE_ID_Z);
          return this;
      }
  
      /**
       * Appends the zone offset, such as '+01:00', to the formatter.
       * <p>
       * This appends an instruction to format/parse the offset ID to the builder.
       * <p>
       * During formatting, the offset is obtained using a mechanism equivalent
       * to querying the temporal with {@link TemporalQueries#offset()}.
       * It will be printed using the format defined below.
       * If the offset cannot be obtained then an exception is thrown unless the
       * section of the formatter is optional.
       * <p>
       * During parsing, the offset is parsed using the format defined below.
       * If the offset cannot be parsed then an exception is thrown unless the
       * section of the formatter is optional.
       * <p>
       * The format of the offset is controlled by a pattern which must be one
       * of the following:
       * <ul>
       * <li>{@code +HH} - hour only, ignoring minute and second
       * <li>{@code +HHmm} - hour, with minute if non-zero, ignoring second, no colon
       * <li>{@code +HH:mm} - hour, with minute if non-zero, ignoring second, with colon
       * <li>{@code +HHMM} - hour and minute, ignoring second, no colon
       * <li>{@code +HH:MM} - hour and minute, ignoring second, with colon
       * <li>{@code +HHMMss} - hour and minute, with second if non-zero, no colon
       * <li>{@code +HH:MM:ss} - hour and minute, with second if non-zero, with colon
       * <li>{@code +HHMMSS} - hour, minute and second, no colon
       * <li>{@code +HH:MM:SS} - hour, minute and second, with colon
       * </ul>
       * The "no offset" text controls what text is printed when the total amount of
       * the offset fields to be output is zero.
       * Example values would be 'Z', '+00:00', 'UTC' or 'GMT'.
       * Three formats are accepted for parsing UTC - the "no offset" text, and the
       * plus and minus versions of zero defined by the pattern.
       *
       * @param pattern  the pattern to use, not null
       * @param noOffsetText  the text to use when the offset is zero, not null
       * @return this, for chaining, not null
       */
      public DateTimeFormatterBuilder appendOffset(String pattern, String noOffsetText) {
          appendInternal(new OffsetIdPrinterParser(pattern, noOffsetText));
          return this;
      }
  
      /**
       * Appends the localized zone offset, such as 'GMT+01:00', to the formatter.
       * <p>
       * This appends a localized zone offset to the builder, the format of the
       * localized offset is controlled by the specified {@link FormatStyle style}
       * to this method:
       * <ul>
       * <li>{@link TextStyle#FULL full} - formats with localized offset text, such
       * as 'GMT, 2-digit hour and minute field, optional second field if non-zero,
       * and colon.
       * <li>{@link TextStyle#SHORT short} - formats with localized offset text,
       * such as 'GMT, hour without leading zero, optional 2-digit minute and
       * second if non-zero, and colon.
       * </ul>
       * <p>
       * During formatting, the offset is obtained using a mechanism equivalent
       * to querying the temporal with {@link TemporalQueries#offset()}.
       * If the offset cannot be obtained then an exception is thrown unless the
       * section of the formatter is optional.
       * <p>
       * During parsing, the offset is parsed using the format defined above.
       * If the offset cannot be parsed then an exception is thrown unless the
       * section of the formatter is optional.
       * <p>
       * @param style  the format style to use, not null
       * @return this, for chaining, not null
       * @throws IllegalArgumentException if style is neither {@link TextStyle#FULL
       * full} nor {@link TextStyle#SHORT short}
       */
      public DateTimeFormatterBuilder appendLocalizedOffset(TextStyle style) {
          Objects.requireNonNull(style, "style");
          if (style != TextStyle.FULL && style != TextStyle.SHORT) {
              throw new IllegalArgumentException("Style must be either full or short");
          }
          appendInternal(new LocalizedOffsetIdPrinterParser(style));
          return this;
      }
  
      //-----------------------------------------------------------------------
      /**
       * Appends the time-zone ID, such as 'Europe/Paris' or '+02:00', to the formatter.
       * <p>
       * This appends an instruction to format/parse the zone ID to the builder.
       * The zone ID is obtained in a strict manner suitable for {@code ZonedDateTime}.
       * By contrast, {@code OffsetDateTime} does not have a zone ID suitable
       * for use with this method, see {@link #appendZoneOrOffsetId()}.
       * <p>
       * During formatting, the zone is obtained using a mechanism equivalent
       * to querying the temporal with {@link TemporalQueries#zoneId()}.
       * It will be printed using the result of {@link ZoneId#getId()}.
       * If the zone cannot be obtained then an exception is thrown unless the
       * section of the formatter is optional.
       * <p>
       * During parsing, the text must match a known zone or offset.
       * There are two types of zone ID, offset-based, such as '+01:30' and
       * region-based, such as 'Europe/London'. These are parsed differently.
       * If the parse starts with '+', '-', 'UT', 'UTC' or 'GMT', then the parser
       * expects an offset-based zone and will not match region-based zones.
       * The offset ID, such as '+02:30', may be at the start of the parse,
       * or prefixed by  'UT', 'UTC' or 'GMT'. The offset ID parsing is
       * equivalent to using {@link #appendOffset(String, String)} using the
       * arguments 'HH:MM:ss' and the no offset string '0'.
       * If the parse starts with 'UT', 'UTC' or 'GMT', and the parser cannot
       * match a following offset ID, then {@link ZoneOffset#UTC} is selected.
       * In all other cases, the list of known region-based zones is used to
       * find the longest available match. If no match is found, and the parse
       * starts with 'Z', then {@code ZoneOffset.UTC} is selected.
       * The parser uses the {@linkplain #parseCaseInsensitive() case sensitive} setting.
       * <p>
       * For example, the following will parse:
       * <pre>
       *   "Europe/London"           -- ZoneId.of("Europe/London")
       *   "Z"                       -- ZoneOffset.UTC
       *   "UT"                      -- ZoneId.of("UT")
       *   "UTC"                     -- ZoneId.of("UTC")
       *   "GMT"                     -- ZoneId.of("GMT")
       *   "+01:30"                  -- ZoneOffset.of("+01:30")
       *   "UT+01:30"                -- ZoneOffset.of("+01:30")
       *   "UTC+01:30"               -- ZoneOffset.of("+01:30")
       *   "GMT+01:30"               -- ZoneOffset.of("+01:30")
       * </pre>
       *
       * @return this, for chaining, not null
       * @see #appendZoneRegionId()
       */
      public DateTimeFormatterBuilder appendZoneId() {
          appendInternal(new ZoneIdPrinterParser(TemporalQueries.zoneId(), "ZoneId()"));
          return this;
      }
  
      /**
       * Appends the time-zone region ID, such as 'Europe/Paris', to the formatter,
       * rejecting the zone ID if it is a {@code ZoneOffset}.
       * <p>
       * This appends an instruction to format/parse the zone ID to the builder
       * only if it is a region-based ID.
       * <p>
       * During formatting, the zone is obtained using a mechanism equivalent
       * to querying the temporal with {@link TemporalQueries#zoneId()}.
       * If the zone is a {@code ZoneOffset} or it cannot be obtained then
       * an exception is thrown unless the section of the formatter is optional.
       * If the zone is not an offset, then the zone will be printed using
       * the zone ID from {@link ZoneId#getId()}.
       * <p>
       * During parsing, the text must match a known zone or offset.
       * There are two types of zone ID, offset-based, such as '+01:30' and
       * region-based, such as 'Europe/London'. These are parsed differently.
       * If the parse starts with '+', '-', 'UT', 'UTC' or 'GMT', then the parser
       * expects an offset-based zone and will not match region-based zones.
       * The offset ID, such as '+02:30', may be at the start of the parse,
       * or prefixed by  'UT', 'UTC' or 'GMT'. The offset ID parsing is
       * equivalent to using {@link #appendOffset(String, String)} using the
       * arguments 'HH:MM:ss' and the no offset string '0'.
       * If the parse starts with 'UT', 'UTC' or 'GMT', and the parser cannot
       * match a following offset ID, then {@link ZoneOffset#UTC} is selected.
       * In all other cases, the list of known region-based zones is used to
       * find the longest available match. If no match is found, and the parse
       * starts with 'Z', then {@code ZoneOffset.UTC} is selected.
       * The parser uses the {@linkplain #parseCaseInsensitive() case sensitive} setting.
       * <p>
       * For example, the following will parse:
       * <pre>
       *   "Europe/London"           -- ZoneId.of("Europe/London")
       *   "Z"                       -- ZoneOffset.UTC
       *   "UT"                      -- ZoneId.of("UT")
       *   "UTC"                     -- ZoneId.of("UTC")
       *   "GMT"                     -- ZoneId.of("GMT")
       *   "+01:30"                  -- ZoneOffset.of("+01:30")
       *   "UT+01:30"                -- ZoneOffset.of("+01:30")
       *   "UTC+01:30"               -- ZoneOffset.of("+01:30")
       *   "GMT+01:30"               -- ZoneOffset.of("+01:30")
       * </pre>
       * <p>
       * Note that this method is identical to {@code appendZoneId()} except
       * in the mechanism used to obtain the zone.
       * Note also that parsing accepts offsets, whereas formatting will never
       * produce one.
       *
       * @return this, for chaining, not null
       * @see #appendZoneId()
       */
      public DateTimeFormatterBuilder appendZoneRegionId() {
          appendInternal(new ZoneIdPrinterParser(QUERY_REGION_ONLY, "ZoneRegionId()"));
          return this;
      }
  
      /**
       * Appends the time-zone ID, such as 'Europe/Paris' or '+02:00', to
       * the formatter, using the best available zone ID.
       * <p>
       * This appends an instruction to format/parse the best available
       * zone or offset ID to the builder.
       * The zone ID is obtained in a lenient manner that first attempts to
       * find a true zone ID, such as that on {@code ZonedDateTime}, and
       * then attempts to find an offset, such as that on {@code OffsetDateTime}.
       * <p>
       * During formatting, the zone is obtained using a mechanism equivalent
       * to querying the temporal with {@link TemporalQueries#zone()}.
       * It will be printed using the result of {@link ZoneId#getId()}.
       * If the zone cannot be obtained then an exception is thrown unless the
       * section of the formatter is optional.
       * <p>
       * During parsing, the text must match a known zone or offset.
       * There are two types of zone ID, offset-based, such as '+01:30' and
       * region-based, such as 'Europe/London'. These are parsed differently.
       * If the parse starts with '+', '-', 'UT', 'UTC' or 'GMT', then the parser
       * expects an offset-based zone and will not match region-based zones.
       * The offset ID, such as '+02:30', may be at the start of the parse,
       * or prefixed by  'UT', 'UTC' or 'GMT'. The offset ID parsing is
       * equivalent to using {@link #appendOffset(String, String)} using the
       * arguments 'HH:MM:ss' and the no offset string '0'.
       * If the parse starts with 'UT', 'UTC' or 'GMT', and the parser cannot
       * match a following offset ID, then {@link ZoneOffset#UTC} is selected.
       * In all other cases, the list of known region-based zones is used to
       * find the longest available match. If no match is found, and the parse
       * starts with 'Z', then {@code ZoneOffset.UTC} is selected.
       * The parser uses the {@linkplain #parseCaseInsensitive() case sensitive} setting.
       * <p>
       * For example, the following will parse:
       * <pre>
       *   "Europe/London"           -- ZoneId.of("Europe/London")
       *   "Z"                       -- ZoneOffset.UTC
       *   "UT"                      -- ZoneId.of("UT")
       *   "UTC"                     -- ZoneId.of("UTC")
       *   "GMT"                     -- ZoneId.of("GMT")
       *   "+01:30"                  -- ZoneOffset.of("+01:30")
       *   "UT+01:30"                -- ZoneOffset.of("UT+01:30")
       *   "UTC+01:30"               -- ZoneOffset.of("UTC+01:30")
       *   "GMT+01:30"               -- ZoneOffset.of("GMT+01:30")
       * </pre>
       * <p>
       * Note that this method is identical to {@code appendZoneId()} except
       * in the mechanism used to obtain the zone.
       *
       * @return this, for chaining, not null
       * @see #appendZoneId()
       */
      public DateTimeFormatterBuilder appendZoneOrOffsetId() {
          appendInternal(new ZoneIdPrinterParser(TemporalQueries.zone(), "ZoneOrOffsetId()"));
          return this;
      }
  
      /**
       * Appends the time-zone name, such as 'British Summer Time', to the formatter.
       * <p>
       * This appends an instruction to format/parse the textual name of the zone to
       * the builder.
       * <p>
       * During formatting, the zone is obtained using a mechanism equivalent
       * to querying the temporal with {@link TemporalQueries#zoneId()}.
       * If the zone is a {@code ZoneOffset} it will be printed using the
       * result of {@link ZoneOffset#getId()}.
       * If the zone is not an offset, the textual name will be looked up
       * for the locale set in the {@link DateTimeFormatter}.
       * If the temporal object being printed represents an instant, then the text
       * will be the summer or winter time text as appropriate.
       * If the lookup for text does not find any suitable result, then the
       * {@link ZoneId#getId() ID} will be printed instead.
       * If the zone cannot be obtained then an exception is thrown unless the
       * section of the formatter is optional.
       * <p>
       * During parsing, either the textual zone name, the zone ID or the offset
       * is accepted. Many textual zone names are not unique, such as CST can be
       * for both "Central Standard Time" and "China Standard Time". In this
       * situation, the zone id will be determined by the region information from
       * formatter's  {@link DateTimeFormatter#getLocale() locale} and the standard
       * zone id for that area, for example, America/New_York for the America Eastern
       * zone. The {@link #appendZoneText(TextStyle, Set)} may be used
       * to specify a set of preferred {@link ZoneId} in this situation.
       *
       * @param textStyle  the text style to use, not null
       * @return this, for chaining, not null
       */
      public DateTimeFormatterBuilder appendZoneText(TextStyle textStyle) {
          appendInternal(new ZoneTextPrinterParser(textStyle, null));
          return this;
      }
  
      /**
       * Appends the time-zone name, such as 'British Summer Time', to the formatter.
       * <p>
       * This appends an instruction to format/parse the textual name of the zone to
       * the builder.
       * <p>
       * During formatting, the zone is obtained using a mechanism equivalent
       * to querying the temporal with {@link TemporalQueries#zoneId()}.
       * If the zone is a {@code ZoneOffset} it will be printed using the
       * result of {@link ZoneOffset#getId()}.
       * If the zone is not an offset, the textual name will be looked up
       * for the locale set in the {@link DateTimeFormatter}.
       * If the temporal object being printed represents an instant, then the text
       * will be the summer or winter time text as appropriate.
       * If the lookup for text does not find any suitable result, then the
       * {@link ZoneId#getId() ID} will be printed instead.
       * If the zone cannot be obtained then an exception is thrown unless the
       * section of the formatter is optional.
       * <p>
       * During parsing, either the textual zone name, the zone ID or the offset
       * is accepted. Many textual zone names are not unique, such as CST can be
       * for both "Central Standard Time" and "China Standard Time". In this
       * situation, the zone id will be determined by the region information from
       * formatter's  {@link DateTimeFormatter#getLocale() locale} and the standard
       * zone id for that area, for example, America/New_York for the America Eastern
       * zone. This method also allows a set of preferred {@link ZoneId} to be
       * specified for parsing. The matched preferred zone id will be used if the
       * textural zone name being parsed is not unique.
       * <p>
       * If the zone cannot be parsed then an exception is thrown unless the
       * section of the formatter is optional.
       *
       * @param textStyle  the text style to use, not null
       * @param preferredZones  the set of preferred zone ids, not null
       * @return this, for chaining, not null
       */
      public DateTimeFormatterBuilder appendZoneText(TextStyle textStyle,
                                                     Set<ZoneId> preferredZones) {
          Objects.requireNonNull(preferredZones, "preferredZones");
          appendInternal(new ZoneTextPrinterParser(textStyle, preferredZones));
          return this;
      }
  
      //-----------------------------------------------------------------------
      /**
       * Appends the chronology ID, such as 'ISO' or 'ThaiBuddhist', to the formatter.
       * <p>
       * This appends an instruction to format/parse the chronology ID to the builder.
       * <p>
       * During formatting, the chronology is obtained using a mechanism equivalent
       * to querying the temporal with {@link TemporalQueries#chronology()}.
       * It will be printed using the result of {@link Chronology#getId()}.
       * If the chronology cannot be obtained then an exception is thrown unless the
       * section of the formatter is optional.
       * <p>
       * During parsing, the chronology is parsed and must match one of the chronologies
       * in {@link Chronology#getAvailableChronologies()}.
       * If the chronology cannot be parsed then an exception is thrown unless the
       * section of the formatter is optional.
       * The parser uses the {@linkplain #parseCaseInsensitive() case sensitive} setting.
       *
       * @return this, for chaining, not null
       */
      public DateTimeFormatterBuilder appendChronologyId() {
          appendInternal(new ChronoPrinterParser(null));
          return this;
      }
  
      /**
       * Appends the chronology name to the formatter.
       * <p>
       * The calendar system name will be output during a format.
       * If the chronology cannot be obtained then an exception will be thrown.
       *
       * @param textStyle  the text style to use, not null
       * @return this, for chaining, not null
       */
      public DateTimeFormatterBuilder appendChronologyText(TextStyle textStyle) {
          Objects.requireNonNull(textStyle, "textStyle");
          appendInternal(new ChronoPrinterParser(textStyle));
          return this;
      }
  
      //-----------------------------------------------------------------------
      /**
       * Appends a localized date-time pattern to the formatter.
       * <p>
       * This appends a localized section to the builder, suitable for outputting
       * a date, time or date-time combination. The format of the localized
       * section is lazily looked up based on four items:
       * <ul>
       * <li>the {@code dateStyle} specified to this method
       * <li>the {@code timeStyle} specified to this method
       * <li>the {@code Locale} of the {@code DateTimeFormatter}
       * <li>the {@code Chronology}, selecting the best available
       * </ul>
       * During formatting, the chronology is obtained from the temporal object
       * being formatted, which may have been overridden by
       * {@link DateTimeFormatter#withChronology(Chronology)}.
       * <p>
       * During parsing, if a chronology has already been parsed, then it is used.
       * Otherwise the default from {@code DateTimeFormatter.withChronology(Chronology)}
       * is used, with {@code IsoChronology} as the fallback.
       * <p>
       * Note that this method provides similar functionality to methods on
       * {@code DateFormat} such as {@link java.text.DateFormat#getDateTimeInstance(int, int)}.
       *
       * @param dateStyle  the date style to use, null means no date required
       * @param timeStyle  the time style to use, null means no time required
       * @return this, for chaining, not null
       * @throws IllegalArgumentException if both the date and time styles are null
       */
      public DateTimeFormatterBuilder appendLocalized(FormatStyle dateStyle, FormatStyle timeStyle) {
          if (dateStyle == null && timeStyle == null) {
              throw new IllegalArgumentException("Either the date or time style must be non-null");
          }
          appendInternal(new LocalizedPrinterParser(dateStyle, timeStyle));
          return this;
      }
  
      //-----------------------------------------------------------------------
      /**
       * Appends a character literal to the formatter.
       * <p>
       * This character will be output during a format.
       *
       * @param literal  the literal to append, not null
       * @return this, for chaining, not null
       */
      public DateTimeFormatterBuilder appendLiteral(char literal) {
          appendInternal(new CharLiteralPrinterParser(literal));
          return this;
      }
  
      /**
       * Appends a string literal to the formatter.
       * <p>
       * This string will be output during a format.
       * <p>
       * If the literal is empty, nothing is added to the formatter.
       *
       * @param literal  the literal to append, not null
       * @return this, for chaining, not null
       */
      public DateTimeFormatterBuilder appendLiteral(String literal) {
          Objects.requireNonNull(literal, "literal");
          if (literal.length() > 0) {
              if (literal.length() == 1) {
                  appendInternal(new CharLiteralPrinterParser(literal.charAt(0)));
              } else {
                  appendInternal(new StringLiteralPrinterParser(literal));
              }
          }
          return this;
      }
  
      //-----------------------------------------------------------------------
      /**
       * Appends all the elements of a formatter to the builder.
       * <p>
       * This method has the same effect as appending each of the constituent
       * parts of the formatter directly to this builder.
       *
       * @param formatter  the formatter to add, not null
       * @return this, for chaining, not null
       */
      public DateTimeFormatterBuilder append(DateTimeFormatter formatter) {
          Objects.requireNonNull(formatter, "formatter");
          appendInternal(formatter.toPrinterParser(false));
          return this;
      }
  
      /**
       * Appends a formatter to the builder which will optionally format/parse.
       * <p>
       * This method has the same effect as appending each of the constituent
       * parts directly to this builder surrounded by an {@link #optionalStart()} and
       * {@link #optionalEnd()}.
       * <p>
       * The formatter will format if data is available for all the fields contained within it.
       * The formatter will parse if the string matches, otherwise no error is returned.
       *
       * @param formatter  the formatter to add, not null
       * @return this, for chaining, not null
       */
      public DateTimeFormatterBuilder appendOptional(DateTimeFormatter formatter) {
          Objects.requireNonNull(formatter, "formatter");
          appendInternal(formatter.toPrinterParser(true));
          return this;
      }
  
      //-----------------------------------------------------------------------
      /**
       * Appends the elements defined by the specified pattern to the builder.
       * <p>
       * All letters 'A' to 'Z' and 'a' to 'z' are reserved as pattern letters.
       * The characters '#', '{' and '}' are reserved for future use.
       * The characters '[' and ']' indicate optional patterns.
       * The following pattern letters are defined:
       * <pre>
       *  Symbol  Meaning                     Presentation      Examples
       *  ------  -------                     ------------      -------
       *   G       era                         text              AD; Anno Domini; A
       *   u       year                        year              2004; 04
       *   y       year-of-era                 year              2004; 04
       *   D       day-of-year                 number            189
       *   M/L     month-of-year               number/text       7; 07; Jul; July; J
       *   d       day-of-month                number            10
       *
       *   Q/q     quarter-of-year             number/text       3; 03; Q3; 3rd quarter
       *   Y       week-based-year             year              1996; 96
       *   w       week-of-week-based-year     number            27
       *   W       week-of-month               number            4
       *   E       day-of-week                 text              Tue; Tuesday; T
       *   e/c     localized day-of-week       number/text       2; 02; Tue; Tuesday; T
       *   F       week-of-month               number            3
       *
       *   a       am-pm-of-day                text              PM
       *   h       clock-hour-of-am-pm (1-12)  number            12
       *   K       hour-of-am-pm (0-11)        number            0
       *   k       clock-hour-of-am-pm (1-24)  number            0
       *
       *   H       hour-of-day (0-23)          number            0
       *   m       minute-of-hour              number            30
       *   s       second-of-minute            number            55
       *   S       fraction-of-second          fraction          978
       *   A       milli-of-day                number            1234
       *   n       nano-of-second              number            987654321
       *   N       nano-of-day                 number            1234000000
       *
       *   V       time-zone ID                zone-id           America/Los_Angeles; Z; -08:30
       *   z       time-zone name              zone-name         Pacific Standard Time; PST
       *   O       localized zone-offset       offset-O          GMT+8; GMT+08:00; UTC-08:00;
       *   X       zone-offset 'Z' for zero    offset-X          Z; -08; -0830; -08:30; -083015; -08:30:15;
       *   x       zone-offset                 offset-x          +0000; -08; -0830; -08:30; -083015; -08:30:15;
       *   Z       zone-offset                 offset-Z          +0000; -0800; -08:00;
       *
       *   p       pad next                    pad modifier      1
       *
       *   '       escape for text             delimiter
       *   ''      single quote                literal           '
       *   [       optional section start
       *   ]       optional section end
       *   #       reserved for future use
       *   {       reserved for future use
       *   }       reserved for future use
       * </pre>
       * <p>
       * The count of pattern letters determine the format.
       * See <a href="DateTimeFormatter.html#patterns">DateTimeFormatter</a> for a user-focused description of the patterns.
       * The following tables define how the pattern letters map to the builder.
       * <p>
       * <b>Date fields</b>: Pattern letters to output a date.
       * <pre>
       *  Pattern  Count  Equivalent builder methods
       *  -------  -----  --------------------------
       *    G       1      appendText(ChronoField.ERA, TextStyle.SHORT)
       *    GG      2      appendText(ChronoField.ERA, TextStyle.SHORT)
       *    GGG     3      appendText(ChronoField.ERA, TextStyle.SHORT)
       *    GGGG    4      appendText(ChronoField.ERA, TextStyle.FULL)
       *    GGGGG   5      appendText(ChronoField.ERA, TextStyle.NARROW)
       *
       *    u       1      appendValue(ChronoField.YEAR, 1, 19, SignStyle.NORMAL);
       *    uu      2      appendValueReduced(ChronoField.YEAR, 2, 2000);
       *    uuu     3      appendValue(ChronoField.YEAR, 3, 19, SignStyle.NORMAL);
       *    u..u    4..n   appendValue(ChronoField.YEAR, n, 19, SignStyle.EXCEEDS_PAD);
       *    y       1      appendValue(ChronoField.YEAR_OF_ERA, 1, 19, SignStyle.NORMAL);
       *    yy      2      appendValueReduced(ChronoField.YEAR_OF_ERA, 2, 2000);
       *    yyy     3      appendValue(ChronoField.YEAR_OF_ERA, 3, 19, SignStyle.NORMAL);
       *    y..y    4..n   appendValue(ChronoField.YEAR_OF_ERA, n, 19, SignStyle.EXCEEDS_PAD);
       *    Y       1      append special localized WeekFields element for numeric week-based-year
       *    YY      2      append special localized WeekFields element for reduced numeric week-based-year 2 digits;
       *    YYY     3      append special localized WeekFields element for numeric week-based-year (3, 19, SignStyle.NORMAL);
       *    Y..Y    4..n   append special localized WeekFields element for numeric week-based-year (n, 19, SignStyle.EXCEEDS_PAD);
       *
       *    Q       1      appendValue(IsoFields.QUARTER_OF_YEAR);
       *    QQ      2      appendValue(IsoFields.QUARTER_OF_YEAR, 2);
       *    QQQ     3      appendText(IsoFields.QUARTER_OF_YEAR, TextStyle.SHORT)
       *    QQQQ    4      appendText(IsoFields.QUARTER_OF_YEAR, TextStyle.FULL)
       *    QQQQQ   5      appendText(IsoFields.QUARTER_OF_YEAR, TextStyle.NARROW)
       *    q       1      appendValue(IsoFields.QUARTER_OF_YEAR);
       *    qq      2      appendValue(IsoFields.QUARTER_OF_YEAR, 2);
       *    qqq     3      appendText(IsoFields.QUARTER_OF_YEAR, TextStyle.SHORT_STANDALONE)
       *    qqqq    4      appendText(IsoFields.QUARTER_OF_YEAR, TextStyle.FULL_STANDALONE)
       *    qqqqq   5      appendText(IsoFields.QUARTER_OF_YEAR, TextStyle.NARROW_STANDALONE)
       *
       *    M       1      appendValue(ChronoField.MONTH_OF_YEAR);
       *    MM      2      appendValue(ChronoField.MONTH_OF_YEAR, 2);
       *    MMM     3      appendText(ChronoField.MONTH_OF_YEAR, TextStyle.SHORT)
       *    MMMM    4      appendText(ChronoField.MONTH_OF_YEAR, TextStyle.FULL)
       *    MMMMM   5      appendText(ChronoField.MONTH_OF_YEAR, TextStyle.NARROW)
       *    L       1      appendValue(ChronoField.MONTH_OF_YEAR);
       *    LL      2      appendValue(ChronoField.MONTH_OF_YEAR, 2);
       *    LLL     3      appendText(ChronoField.MONTH_OF_YEAR, TextStyle.SHORT_STANDALONE)
       *    LLLL    4      appendText(ChronoField.MONTH_OF_YEAR, TextStyle.FULL_STANDALONE)
       *    LLLLL   5      appendText(ChronoField.MONTH_OF_YEAR, TextStyle.NARROW_STANDALONE)
       *
       *    w       1      append special localized WeekFields element for numeric week-of-year
       *    ww      2      append special localized WeekFields element for numeric week-of-year, zero-padded
       *    W       1      append special localized WeekFields element for numeric week-of-month
       *    d       1      appendValue(ChronoField.DAY_OF_MONTH)
       *    dd      2      appendValue(ChronoField.DAY_OF_MONTH, 2)
       *    D       1      appendValue(ChronoField.DAY_OF_YEAR)
       *    DD      2      appendValue(ChronoField.DAY_OF_YEAR, 2)
       *    DDD     3      appendValue(ChronoField.DAY_OF_YEAR, 3)
       *    F       1      appendValue(ChronoField.ALIGNED_DAY_OF_WEEK_IN_MONTH)
       *    E       1      appendText(ChronoField.DAY_OF_WEEK, TextStyle.SHORT)
       *    EE      2      appendText(ChronoField.DAY_OF_WEEK, TextStyle.SHORT)
       *    EEE     3      appendText(ChronoField.DAY_OF_WEEK, TextStyle.SHORT)
       *    EEEE    4      appendText(ChronoField.DAY_OF_WEEK, TextStyle.FULL)
       *    EEEEE   5      appendText(ChronoField.DAY_OF_WEEK, TextStyle.NARROW)
       *    e       1      append special localized WeekFields element for numeric day-of-week
       *    ee      2      append special localized WeekFields element for numeric day-of-week, zero-padded
       *    eee     3      appendText(ChronoField.DAY_OF_WEEK, TextStyle.SHORT)
       *    eeee    4      appendText(ChronoField.DAY_OF_WEEK, TextStyle.FULL)
       *    eeeee   5      appendText(ChronoField.DAY_OF_WEEK, TextStyle.NARROW)
       *    c       1      append special localized WeekFields element for numeric day-of-week
       *    ccc     3      appendText(ChronoField.DAY_OF_WEEK, TextStyle.SHORT_STANDALONE)
       *    cccc    4      appendText(ChronoField.DAY_OF_WEEK, TextStyle.FULL_STANDALONE)
       *    ccccc   5      appendText(ChronoField.DAY_OF_WEEK, TextStyle.NARROW_STANDALONE)
       * </pre>
       * <p>
       * <b>Time fields</b>: Pattern letters to output a time.
       * <pre>
       *  Pattern  Count  Equivalent builder methods
       *  -------  -----  --------------------------
       *    a       1      appendText(ChronoField.AMPM_OF_DAY, TextStyle.SHORT)
       *    h       1      appendValue(ChronoField.CLOCK_HOUR_OF_AMPM)
       *    hh      2      appendValue(ChronoField.CLOCK_HOUR_OF_AMPM, 2)
       *    H       1      appendValue(ChronoField.HOUR_OF_DAY)
       *    HH      2      appendValue(ChronoField.HOUR_OF_DAY, 2)
       *    k       1      appendValue(ChronoField.CLOCK_HOUR_OF_DAY)
       *    kk      2      appendValue(ChronoField.CLOCK_HOUR_OF_DAY, 2)
       *    K       1      appendValue(ChronoField.HOUR_OF_AMPM)
       *    KK      2      appendValue(ChronoField.HOUR_OF_AMPM, 2)
       *    m       1      appendValue(ChronoField.MINUTE_OF_HOUR)
       *    mm      2      appendValue(ChronoField.MINUTE_OF_HOUR, 2)
       *    s       1      appendValue(ChronoField.SECOND_OF_MINUTE)
       *    ss      2      appendValue(ChronoField.SECOND_OF_MINUTE, 2)
       *
       *    S..S    1..n   appendFraction(ChronoField.NANO_OF_SECOND, n, n, false)
       *    A       1      appendValue(ChronoField.MILLI_OF_DAY)
       *    A..A    2..n   appendValue(ChronoField.MILLI_OF_DAY, n)
       *    n       1      appendValue(ChronoField.NANO_OF_SECOND)
       *    n..n    2..n   appendValue(ChronoField.NANO_OF_SECOND, n)
       *    N       1      appendValue(ChronoField.NANO_OF_DAY)
       *    N..N    2..n   appendValue(ChronoField.NANO_OF_DAY, n)
       * </pre>
       * <p>
       * <b>Zone ID</b>: Pattern letters to output {@code ZoneId}.
       * <pre>
       *  Pattern  Count  Equivalent builder methods
       *  -------  -----  --------------------------
       *    VV      2      appendZoneId()
       *    z       1      appendZoneText(TextStyle.SHORT)
       *    zz      2      appendZoneText(TextStyle.SHORT)
       *    zzz     3      appendZoneText(TextStyle.SHORT)
       *    zzzz    4      appendZoneText(TextStyle.FULL)
       * </pre>
       * <p>
       * <b>Zone offset</b>: Pattern letters to output {@code ZoneOffset}.
       * <pre>
       *  Pattern  Count  Equivalent builder methods
       *  -------  -----  --------------------------
       *    O       1      appendLocalizedOffsetPrefixed(TextStyle.SHORT);
       *    OOOO    4      appendLocalizedOffsetPrefixed(TextStyle.FULL);
       *    X       1      appendOffset("+HHmm","Z")
       *    XX      2      appendOffset("+HHMM","Z")
       *    XXX     3      appendOffset("+HH:MM","Z")
       *    XXXX    4      appendOffset("+HHMMss","Z")
       *    XXXXX   5      appendOffset("+HH:MM:ss","Z")
       *    x       1      appendOffset("+HHmm","+00")
       *    xx      2      appendOffset("+HHMM","+0000")
       *    xxx     3      appendOffset("+HH:MM","+00:00")
       *    xxxx    4      appendOffset("+HHMMss","+0000")
       *    xxxxx   5      appendOffset("+HH:MM:ss","+00:00")
       *    Z       1      appendOffset("+HHMM","+0000")
       *    ZZ      2      appendOffset("+HHMM","+0000")
       *    ZZZ     3      appendOffset("+HHMM","+0000")
       *    ZZZZ    4      appendLocalizedOffset(TextStyle.FULL);
       *    ZZZZZ   5      appendOffset("+HH:MM:ss","Z")
       * </pre>
       * <p>
       * <b>Modifiers</b>: Pattern letters that modify the rest of the pattern:
       * <pre>
       *  Pattern  Count  Equivalent builder methods
       *  -------  -----  --------------------------
       *    [       1      optionalStart()
       *    ]       1      optionalEnd()
       *    p..p    1..n   padNext(n)
       * </pre>
       * <p>
       * Any sequence of letters not specified above, unrecognized letter or
       * reserved character will throw an exception.
       * Future versions may add to the set of patterns.
       * It is recommended to use single quotes around all characters that you want
       * to output directly to ensure that future changes do not break your application.
       * <p>
       * Note that the pattern string is similar, but not identical, to
       * {@link java.text.SimpleDateFormat SimpleDateFormat}.
       * The pattern string is also similar, but not identical, to that defined by the
       * Unicode Common Locale Data Repository (CLDR/LDML).
       * Pattern letters 'X' and 'u' are aligned with Unicode CLDR/LDML.
       * By contrast, {@code SimpleDateFormat} uses 'u' for the numeric day of week.
       * Pattern letters 'y' and 'Y' parse years of two digits and more than 4 digits differently.
       * Pattern letters 'n', 'A', 'N', and 'p' are added.
       * Number types will reject large numbers.
       *
       * @param pattern  the pattern to add, not null
       * @return this, for chaining, not null
       * @throws IllegalArgumentException if the pattern is invalid
       */
      public DateTimeFormatterBuilder appendPattern(String pattern) {
          Objects.requireNonNull(pattern, "pattern");
          parsePattern(pattern);
          return this;
      }
  
      private void parsePattern(String pattern) {
          for (int pos = 0; pos < pattern.length(); pos++) {
              char cur = pattern.charAt(pos);
              if ((cur >= 'A' && cur <= 'Z') || (cur >= 'a' && cur <= 'z')) {
                  int start = pos++;
                  for ( ; pos < pattern.length() && pattern.charAt(pos) == cur; pos++);  // short loop
                  int count = pos - start;
                  // padding
                  if (cur == 'p') {
                      int pad = 0;
                      if (pos < pattern.length()) {
                          cur = pattern.charAt(pos);
                          if ((cur >= 'A' && cur <= 'Z') || (cur >= 'a' && cur <= 'z')) {
                              pad = count;
                              start = pos++;
                              for ( ; pos < pattern.length() && pattern.charAt(pos) == cur; pos++);  // short loop
                              count = pos - start;
                          }
                      }
                      if (pad == 0) {
                          throw new IllegalArgumentException(
                                  "Pad letter 'p' must be followed by valid pad pattern: " + pattern);
                      }
                      padNext(pad); // pad and continue parsing
                  }
                  // main rules
                  TemporalField field = FIELD_MAP.get(cur);
                  if (field != null) {
                      parseField(cur, count, field);
                  } else if (cur == 'z') {
                      if (count > 4) {
                          throw new IllegalArgumentException("Too many pattern letters: " + cur);
                      } else if (count == 4) {
                          appendZoneText(TextStyle.FULL);
                      } else {
                          appendZoneText(TextStyle.SHORT);
                      }
                  } else if (cur == 'V') {
                      if (count != 2) {
                          throw new IllegalArgumentException("Pattern letter count must be 2: " + cur);
                      }
                      appendZoneId();
                  } else if (cur == 'Z') {
                      if (count < 4) {
                          appendOffset("+HHMM", "+0000");
                      } else if (count == 4) {
                          appendLocalizedOffset(TextStyle.FULL);
                      } else if (count == 5) {
                          appendOffset("+HH:MM:ss","Z");
                      } else {
                          throw new IllegalArgumentException("Too many pattern letters: " + cur);
                      }
                  } else if (cur == 'O') {
                      if (count == 1) {
                          appendLocalizedOffset(TextStyle.SHORT);
                      } else if (count == 4) {
                          appendLocalizedOffset(TextStyle.FULL);
                      } else {
                          throw new IllegalArgumentException("Pattern letter count must be 1 or 4: " + cur);
                      }
                  } else if (cur == 'X') {
                      if (count > 5) {
                          throw new IllegalArgumentException("Too many pattern letters: " + cur);
                      }
                      appendOffset(OffsetIdPrinterParser.PATTERNS[count + (count == 1 ? 0 : 1)], "Z");
                  } else if (cur == 'x') {
                      if (count > 5) {
                          throw new IllegalArgumentException("Too many pattern letters: " + cur);
                      }
                      String zero = (count == 1 ? "+00" : (count % 2 == 0 ? "+0000" : "+00:00"));
                      appendOffset(OffsetIdPrinterParser.PATTERNS[count + (count == 1 ? 0 : 1)], zero);
                  } else if (cur == 'W') {
                      // Fields defined by Locale
                      if (count > 1) {
                          throw new IllegalArgumentException("Too many pattern letters: " + cur);
                      }
                      appendInternal(new WeekBasedFieldPrinterParser(cur, count));
                  } else if (cur == 'w') {
                      // Fields defined by Locale
                      if (count > 2) {
                          throw new IllegalArgumentException("Too many pattern letters: " + cur);
                      }
                      appendInternal(new WeekBasedFieldPrinterParser(cur, count));
                  } else if (cur == 'Y') {
                      // Fields defined by Locale
                      appendInternal(new WeekBasedFieldPrinterParser(cur, count));
                  } else {
                      throw new IllegalArgumentException("Unknown pattern letter: " + cur);
                  }
                  pos--;
  
              } else if (cur == '\'') {
                  // parse literals
                  int start = pos++;
                  for ( ; pos < pattern.length(); pos++) {
                      if (pattern.charAt(pos) == '\'') {
                          if (pos + 1 < pattern.length() && pattern.charAt(pos + 1) == '\'') {
                              pos++;
                          } else {
                              break;  // end of literal
                          }
                      }
                  }
                  if (pos >= pattern.length()) {
                      throw new IllegalArgumentException("Pattern ends with an incomplete string literal: " + pattern);
                  }
                  String str = pattern.substring(start + 1, pos);
                  if (str.length() == 0) {
                      appendLiteral('\'');
                  } else {
                      appendLiteral(str.replace("''", "'"));
                  }
  
              } else if (cur == '[') {
                  optionalStart();
  
              } else if (cur == ']') {
                  if (active.parent == null) {
                      throw new IllegalArgumentException("Pattern invalid as it contains ] without previous [");
                  }
                  optionalEnd();
  
              } else if (cur == '{' || cur == '}' || cur == '#') {
                  throw new IllegalArgumentException("Pattern includes reserved character: '" + cur + "'");
              } else {
                  appendLiteral(cur);
              }
          }
      }
  
      @SuppressWarnings("fallthrough")
      private void parseField(char cur, int count, TemporalField field) {
          boolean standalone = false;
          switch (cur) {
              case 'u':
              case 'y':
                  if (count == 2) {
                      appendValueReduced(field, 2, 2, ReducedPrinterParser.BASE_DATE);
                  } else if (count < 4) {
                      appendValue(field, count, 19, SignStyle.NORMAL);
                  } else {
                      appendValue(field, count, 19, SignStyle.EXCEEDS_PAD);
                  }
                  break;
              case 'c':
                  if (count == 2) {
                      throw new IllegalArgumentException("Invalid pattern \"cc\"");
                  }
                  /*fallthrough*/
              case 'L':
              case 'q':
                  standalone = true;
                  /*fallthrough*/
              case 'M':
              case 'Q':
              case 'E':
              case 'e':
                  switch (count) {
                      case 1:
                      case 2:
                          if (cur == 'c' || cur == 'e') {
                              appendInternal(new WeekBasedFieldPrinterParser(cur, count));
                          } else if (cur == 'E') {
                              appendText(field, TextStyle.SHORT);
                          } else {
                              if (count == 1) {
                                  appendValue(field);
                              } else {
                                  appendValue(field, 2);
                              }
                          }
                          break;
                      case 3:
                          appendText(field, standalone ? TextStyle.SHORT_STANDALONE : TextStyle.SHORT);
                          break;
                      case 4:
                          appendText(field, standalone ? TextStyle.FULL_STANDALONE : TextStyle.FULL);
                          break;
                      case 5:
                          appendText(field, standalone ? TextStyle.NARROW_STANDALONE : TextStyle.NARROW);
                          break;
                      default:
                          throw new IllegalArgumentException("Too many pattern letters: " + cur);
                  }
                  break;
              case 'a':
                  if (count == 1) {
                      appendText(field, TextStyle.SHORT);
                  } else {
                      throw new IllegalArgumentException("Too many pattern letters: " + cur);
                  }
                  break;
              case 'G':
                  switch (count) {
                      case 1:
                      case 2:
                      case 3:
                          appendText(field, TextStyle.SHORT);
                          break;
                      case 4:
                          appendText(field, TextStyle.FULL);
                          break;
                      case 5:
                          appendText(field, TextStyle.NARROW);
                          break;
                      default:
                          throw new IllegalArgumentException("Too many pattern letters: " + cur);
                  }
                  break;
              case 'S':
                  appendFraction(NANO_OF_SECOND, count, count, false);
                  break;
              case 'F':
                  if (count == 1) {
                      appendValue(field);
                  } else {
                      throw new IllegalArgumentException("Too many pattern letters: " + cur);
                  }
                  break;
              case 'd':
              case 'h':
              case 'H':
              case 'k':
              case 'K':
              case 'm':
              case 's':
                  if (count == 1) {
                      appendValue(field);
                  } else if (count == 2) {
                      appendValue(field, count);
                  } else {
                      throw new IllegalArgumentException("Too many pattern letters: " + cur);
                  }
                  break;
              case 'D':
                  if (count == 1) {
                      appendValue(field);
                  } else if (count <= 3) {
                      appendValue(field, count);
                  } else {
                      throw new IllegalArgumentException("Too many pattern letters: " + cur);
                  }
                  break;
              default:
                  if (count == 1) {
                      appendValue(field);
                  } else {
                      appendValue(field, count);
                  }
                  break;
          }
      }
  
      /** Map of letters to fields. */
      private static final Map<Character, TemporalField> FIELD_MAP = new HashMap<>();
      static {
          // SDF = SimpleDateFormat
          FIELD_MAP.put('G', ChronoField.ERA);                       // SDF, LDML (different to both for 1/2 chars)
          FIELD_MAP.put('y', ChronoField.YEAR_OF_ERA);               // SDF, LDML
          FIELD_MAP.put('u', ChronoField.YEAR);                      // LDML (different in SDF)
          FIELD_MAP.put('Q', IsoFields.QUARTER_OF_YEAR);             // LDML (removed quarter from 310)
          FIELD_MAP.put('q', IsoFields.QUARTER_OF_YEAR);             // LDML (stand-alone)
          FIELD_MAP.put('M', ChronoField.MONTH_OF_YEAR);             // SDF, LDML
          FIELD_MAP.put('L', ChronoField.MONTH_OF_YEAR);             // SDF, LDML (stand-alone)
          FIELD_MAP.put('D', ChronoField.DAY_OF_YEAR);               // SDF, LDML
          FIELD_MAP.put('d', ChronoField.DAY_OF_MONTH);              // SDF, LDML
          FIELD_MAP.put('F', ChronoField.ALIGNED_DAY_OF_WEEK_IN_MONTH);  // SDF, LDML
          FIELD_MAP.put('E', ChronoField.DAY_OF_WEEK);               // SDF, LDML (different to both for 1/2 chars)
          FIELD_MAP.put('c', ChronoField.DAY_OF_WEEK);               // LDML (stand-alone)
          FIELD_MAP.put('e', ChronoField.DAY_OF_WEEK);               // LDML (needs localized week number)
          FIELD_MAP.put('a', ChronoField.AMPM_OF_DAY);               // SDF, LDML
          FIELD_MAP.put('H', ChronoField.HOUR_OF_DAY);               // SDF, LDML
          FIELD_MAP.put('k', ChronoField.CLOCK_HOUR_OF_DAY);         // SDF, LDML
          FIELD_MAP.put('K', ChronoField.HOUR_OF_AMPM);              // SDF, LDML
          FIELD_MAP.put('h', ChronoField.CLOCK_HOUR_OF_AMPM);        // SDF, LDML
          FIELD_MAP.put('m', ChronoField.MINUTE_OF_HOUR);            // SDF, LDML
          FIELD_MAP.put('s', ChronoField.SECOND_OF_MINUTE);          // SDF, LDML
          FIELD_MAP.put('S', ChronoField.NANO_OF_SECOND);            // LDML (SDF uses milli-of-second number)
          FIELD_MAP.put('A', ChronoField.MILLI_OF_DAY);              // LDML
          FIELD_MAP.put('n', ChronoField.NANO_OF_SECOND);            // 310 (proposed for LDML)
          FIELD_MAP.put('N', ChronoField.NANO_OF_DAY);               // 310 (proposed for LDML)
          // 310 - z - time-zone names, matches LDML and SimpleDateFormat 1 to 4
          // 310 - Z - matches SimpleDateFormat and LDML
          // 310 - V - time-zone id, matches LDML
          // 310 - p - prefix for padding
          // 310 - X - matches LDML, almost matches SDF for 1, exact match 2&3, extended 4&5
          // 310 - x - matches LDML
          // 310 - w, W, and Y are localized forms matching LDML
          // LDML - U - cycle year name, not supported by 310 yet
          // LDML - l - deprecated
          // LDML - j - not relevant
          // LDML - g - modified-julian-day
          // LDML - v,V - extended time-zone names
      }
  
      //-----------------------------------------------------------------------
      /**
       * Causes the next added printer/parser to pad to a fixed width using a space.
       * <p>
       * This padding will pad to a fixed width using spaces.
       * <p>
       * During formatting, the decorated element will be output and then padded
       * to the specified width. An exception will be thrown during formatting if
       * the pad width is exceeded.
       * <p>
       * During parsing, the padding and decorated element are parsed.
       * If parsing is lenient, then the pad width is treated as a maximum.
       * The padding is parsed greedily. Thus, if the decorated element starts with
       * the pad character, it will not be parsed.
       *
       * @param padWidth  the pad width, 1 or greater
       * @return this, for chaining, not null
       * @throws IllegalArgumentException if pad width is too small
       */
      public DateTimeFormatterBuilder padNext(int padWidth) {
          return padNext(padWidth, ' ');
      }
  
      /**
       * Causes the next added printer/parser to pad to a fixed width.
       * <p>
       * This padding is intended for padding other than zero-padding.
       * Zero-padding should be achieved using the appendValue methods.
       * <p>
       * During formatting, the decorated element will be output and then padded
       * to the specified width. An exception will be thrown during formatting if
       * the pad width is exceeded.
       * <p>
       * During parsing, the padding and decorated element are parsed.
       * If parsing is lenient, then the pad width is treated as a maximum.
       * If parsing is case insensitive, then the pad character is matched ignoring case.
       * The padding is parsed greedily. Thus, if the decorated element starts with
       * the pad character, it will not be parsed.
       *
       * @param padWidth  the pad width, 1 or greater
       * @param padChar  the pad character
       * @return this, for chaining, not null
       * @throws IllegalArgumentException if pad width is too small
       */
      public DateTimeFormatterBuilder padNext(int padWidth, char padChar) {
          if (padWidth < 1) {
              throw new IllegalArgumentException("The pad width must be at least one but was " + padWidth);
          }
          active.padNextWidth = padWidth;
          active.padNextChar = padChar;
          active.valueParserIndex = -1;
          return this;
      }
  
      //-----------------------------------------------------------------------
      /**
       * Mark the start of an optional section.
       * <p>
       * The output of formatting can include optional sections, which may be nested.
       * An optional section is started by calling this method and ended by calling
       * {@link #optionalEnd()} or by ending the build process.
       * <p>
       * All elements in the optional section are treated as optional.
       * During formatting, the section is only output if data is available in the
       * {@code TemporalAccessor} for all the elements in the section.
       * During parsing, the whole section may be missing from the parsed string.
       * <p>
       * For example, consider a builder setup as
       * {@code builder.appendValue(HOUR_OF_DAY,2).optionalStart().appendValue(MINUTE_OF_HOUR,2)}.
       * The optional section ends automatically at the end of the builder.
       * During formatting, the minute will only be output if its value can be obtained from the date-time.
       * During parsing, the input will be successfully parsed whether the minute is present or not.
       *
       * @return this, for chaining, not null
       */
      public DateTimeFormatterBuilder optionalStart() {
          active.valueParserIndex = -1;
          active = new DateTimeFormatterBuilder(active, true);
          return this;
      }
  
      /**
       * Ends an optional section.
       * <p>
       * The output of formatting can include optional sections, which may be nested.
       * An optional section is started by calling {@link #optionalStart()} and ended
       * using this method (or at the end of the builder).
       * <p>
       * Calling this method without having previously called {@code optionalStart}
       * will throw an exception.
       * Calling this method immediately after calling {@code optionalStart} has no effect
       * on the formatter other than ending the (empty) optional section.
       * <p>
       * All elements in the optional section are treated as optional.
       * During formatting, the section is only output if data is available in the
       * {@code TemporalAccessor} for all the elements in the section.
       * During parsing, the whole section may be missing from the parsed string.
       * <p>
       * For example, consider a builder setup as
       * {@code builder.appendValue(HOUR_OF_DAY,2).optionalStart().appendValue(MINUTE_OF_HOUR,2).optionalEnd()}.
       * During formatting, the minute will only be output if its value can be obtained from the date-time.
       * During parsing, the input will be successfully parsed whether the minute is present or not.
       *
       * @return this, for chaining, not null
       * @throws IllegalStateException if there was no previous call to {@code optionalStart}
       */
      public DateTimeFormatterBuilder optionalEnd() {
          if (active.parent == null) {
              throw new IllegalStateException("Cannot call optionalEnd() as there was no previous call to optionalStart()");
          }
          if (active.printerParsers.size() > 0) {
              CompositePrinterParser cpp = new CompositePrinterParser(active.printerParsers, active.optional);
              active = active.parent;
              appendInternal(cpp);
          } else {
              active = active.parent;
          }
          return this;
      }
  
      //-----------------------------------------------------------------------
      /**
       * Appends a printer and/or parser to the internal list handling padding.
       *
       * @param pp  the printer-parser to add, not null
       * @return the index into the active parsers list
       */
      private int appendInternal(DateTimePrinterParser pp) {
          Objects.requireNonNull(pp, "pp");
          if (active.padNextWidth > 0) {
              if (pp != null) {
                  pp = new PadPrinterParserDecorator(pp, active.padNextWidth, active.padNextChar);
              }
              active.padNextWidth = 0;
              active.padNextChar = 0;
          }
          active.printerParsers.add(pp);
          active.valueParserIndex = -1;
          return active.printerParsers.size() - 1;
      }
  
      //-----------------------------------------------------------------------
      /**
       * Completes this builder by creating the {@code DateTimeFormatter}
       * using the default locale.
       * <p>
       * This will create a formatter with the {@linkplain Locale#getDefault(Locale.Category) default FORMAT locale}.
       * Numbers will be printed and parsed using the standard DecimalStyle.
       * The resolver style will be {@link ResolverStyle#SMART SMART}.
       * <p>
       * Calling this method will end any open optional sections by repeatedly
       * calling {@link #optionalEnd()} before creating the formatter.
       * <p>
       * This builder can still be used after creating the formatter if desired,
       * although the state may have been changed by calls to {@code optionalEnd}.
       *
       * @return the created formatter, not null
       */
      public DateTimeFormatter toFormatter() {
          return toFormatter(Locale.getDefault(Locale.Category.FORMAT));
      }
  
      /**
       * Completes this builder by creating the {@code DateTimeFormatter}
       * using the specified locale.
       * <p>
       * This will create a formatter with the specified locale.
       * Numbers will be printed and parsed using the standard DecimalStyle.
       * The resolver style will be {@link ResolverStyle#SMART SMART}.
       * <p>
       * Calling this method will end any open optional sections by repeatedly
       * calling {@link #optionalEnd()} before creating the formatter.
       * <p>
       * This builder can still be used after creating the formatter if desired,
       * although the state may have been changed by calls to {@code optionalEnd}.
       *
       * @param locale  the locale to use for formatting, not null
       * @return the created formatter, not null
       */
      public DateTimeFormatter toFormatter(Locale locale) {
          return toFormatter(locale, ResolverStyle.SMART, null);
      }
  
      /**
       * Completes this builder by creating the formatter.
       * This uses the default locale.
       *
       * @param resolverStyle  the resolver style to use, not null
       * @return the created formatter, not null
       */
      DateTimeFormatter toFormatter(ResolverStyle resolverStyle, Chronology chrono) {
          return toFormatter(Locale.getDefault(Locale.Category.FORMAT), resolverStyle, chrono);
      }
  
      /**
       * Completes this builder by creating the formatter.
       *
       * @param locale  the locale to use for formatting, not null
       * @param chrono  the chronology to use, may be null
       * @return the created formatter, not null
       */
      private DateTimeFormatter toFormatter(Locale locale, ResolverStyle resolverStyle, Chronology chrono) {
          Objects.requireNonNull(locale, "locale");
          while (active.parent != null) {
              optionalEnd();
          }
          CompositePrinterParser pp = new CompositePrinterParser(printerParsers, false);
          return new DateTimeFormatter(pp, locale, DecimalStyle.STANDARD,
                  resolverStyle, null, chrono, null);
      }
  
      //-----------------------------------------------------------------------
      /**
       * Strategy for formatting/parsing date-time information.
       * <p>
       * The printer may format any part, or the whole, of the input date-time object.
       * Typically, a complete format is constructed from a number of smaller
       * units, each outputting a single field.
       * <p>
       * The parser may parse any piece of text from the input, storing the result
       * in the context. Typically, each individual parser will just parse one
       * field, such as the day-of-month, storing the value in the context.
       * Once the parse is complete, the caller will then resolve the parsed values
       * to create the desired object, such as a {@code LocalDate}.
       * <p>
       * The parse position will be updated during the parse. Parsing will start at
       * the specified index and the return value specifies the new parse position
       * for the next parser. If an error occurs, the returned index will be negative
       * and will have the error position encoded using the complement operator.
       *
       * @implSpec
       * This interface must be implemented with care to ensure other classes operate correctly.
       * All implementations that can be instantiated must be final, immutable and thread-safe.
       * <p>
       * The context is not a thread-safe object and a new instance will be created
       * for each format that occurs. The context must not be stored in an instance
       * variable or shared with any other threads.
       */
      interface DateTimePrinterParser {
  
          /**
           * Prints the date-time object to the buffer.
           * <p>
           * The context holds information to use during the format.
           * It also contains the date-time information to be printed.
           * <p>
           * The buffer must not be mutated beyond the content controlled by the implementation.
           *
           * @param context  the context to format using, not null
           * @param buf  the buffer to append to, not null
           * @return false if unable to query the value from the date-time, true otherwise
           * @throws DateTimeException if the date-time cannot be printed successfully
           */
          boolean format(DateTimePrintContext context, StringBuilder buf);
  
          /**
           * Parses text into date-time information.
           * <p>
           * The context holds information to use during the parse.
           * It is also used to store the parsed date-time information.
           *
           * @param context  the context to use and parse into, not null
           * @param text  the input text to parse, not null
           * @param position  the position to start parsing at, from 0 to the text length
           * @return the new parse position, where negative means an error with the
           *  error position encoded using the complement ~ operator
           * @throws NullPointerException if the context or text is null
           * @throws IndexOutOfBoundsException if the position is invalid
           */
          int parse(DateTimeParseContext context, CharSequence text, int position);
      }
  
      //-----------------------------------------------------------------------
      /**
       * Composite printer and parser.
       */
      static final class CompositePrinterParser implements DateTimePrinterParser {
          private final DateTimePrinterParser[] printerParsers;
          private final boolean optional;
  
          CompositePrinterParser(List<DateTimePrinterParser> printerParsers, boolean optional) {
              this(printerParsers.toArray(new DateTimePrinterParser[printerParsers.size()]), optional);
          }
  
          CompositePrinterParser(DateTimePrinterParser[] printerParsers, boolean optional) {
              this.printerParsers = printerParsers;
              this.optional = optional;
          }
  
          /**
           * Returns a copy of this printer-parser with the optional flag changed.
           *
           * @param optional  the optional flag to set in the copy
           * @return the new printer-parser, not null
           */
          public CompositePrinterParser withOptional(boolean optional) {
              if (optional == this.optional) {
                  return this;
              }
              return new CompositePrinterParser(printerParsers, optional);
          }
  
          @Override
          public boolean format(DateTimePrintContext context, StringBuilder buf) {
              int length = buf.length();
              if (optional) {
                  context.startOptional();
              }
              try {
                  for (DateTimePrinterParser pp : printerParsers) {
                      if (pp.format(context, buf) == false) {
                          buf.setLength(length);  // reset buffer
                          return true;
                      }
                  }
              } finally {
                  if (optional) {
                      context.endOptional();
                  }
              }
              return true;
          }
  
          @Override
          public int parse(DateTimeParseContext context, CharSequence text, int position) {
              if (optional) {
                  context.startOptional();
                  int pos = position;
                  for (DateTimePrinterParser pp : printerParsers) {
                      pos = pp.parse(context, text, pos);
                      if (pos < 0) {
                          context.endOptional(false);
                          return position;  // return original position
                      }
                  }
                  context.endOptional(true);
                  return pos;
              } else {
                  for (DateTimePrinterParser pp : printerParsers) {
                      position = pp.parse(context, text, position);
                      if (position < 0) {
                          break;
                      }
                  }
                  return position;
              }
          }
  
          @Override
          public String toString() {
              StringBuilder buf = new StringBuilder();
              if (printerParsers != null) {
                  buf.append(optional ? "[" : "(");
                  for (DateTimePrinterParser pp : printerParsers) {
                      buf.append(pp);
                  }
                  buf.append(optional ? "]" : ")");
              }
              return buf.toString();
          }
      }
  
      //-----------------------------------------------------------------------
      /**
       * Pads the output to a fixed width.
       */
      static final class PadPrinterParserDecorator implements DateTimePrinterParser {
          private final DateTimePrinterParser printerParser;
          private final int padWidth;
          private final char padChar;
  
          /**
           * Constructor.
           *
           * @param printerParser  the printer, not null
           * @param padWidth  the width to pad to, 1 or greater
           * @param padChar  the pad character
           */
          PadPrinterParserDecorator(DateTimePrinterParser printerParser, int padWidth, char padChar) {
              // input checked by DateTimeFormatterBuilder
              this.printerParser = printerParser;
              this.padWidth = padWidth;
              this.padChar = padChar;
          }
  
          @Override
          public boolean format(DateTimePrintContext context, StringBuilder buf) {
              int preLen = buf.length();
              if (printerParser.format(context, buf) == false) {
                  return false;
              }
              int len = buf.length() - preLen;
              if (len > padWidth) {
                  throw new DateTimeException(
                      "Cannot print as output of " + len + " characters exceeds pad width of " + padWidth);
              }
              for (int i = 0; i < padWidth - len; i++) {
                  buf.insert(preLen, padChar);
              }
              return true;
          }
  
          @Override
          public int parse(DateTimeParseContext context, CharSequence text, int position) {
              // cache context before changed by decorated parser
              final boolean strict = context.isStrict();
              // parse
              if (position > text.length()) {
                  throw new IndexOutOfBoundsException();
              }
              if (position == text.length()) {
                  return ~position;  // no more characters in the string
              }
              int endPos = position + padWidth;
              if (endPos > text.length()) {
                  if (strict) {
                      return ~position;  // not enough characters in the string to meet the parse width
                  }
                  endPos = text.length();
              }
              int pos = position;
              while (pos < endPos && context.charEquals(text.charAt(pos), padChar)) {
                  pos++;
              }
              text = text.subSequence(0, endPos);
              int resultPos = printerParser.parse(context, text, pos);
              if (resultPos != endPos && strict) {
                  return ~(position + pos);  // parse of decorated field didn't parse to the end
              }
              return resultPos;
          }
  
          @Override
          public String toString() {
              return "Pad(" + printerParser + "," + padWidth + (padChar == ' ' ? ")" : ",'" + padChar + "')");
          }
      }
  
      //-----------------------------------------------------------------------
      /**
       * Enumeration to apply simple parse settings.
       */
      static enum SettingsParser implements DateTimePrinterParser {
          SENSITIVE,
          INSENSITIVE,
          STRICT,
          LENIENT;
  
          @Override
          public boolean format(DateTimePrintContext context, StringBuilder buf) {
              return true;  // nothing to do here
          }
  
          @Override
          public int parse(DateTimeParseContext context, CharSequence text, int position) {
              // using ordinals to avoid javac synthetic inner class
              switch (ordinal()) {
                  case 0: context.setCaseSensitive(true); break;
                  case 1: context.setCaseSensitive(false); break;
                  case 2: context.setStrict(true); break;
                  case 3: context.setStrict(false); break;
              }
              return position;
          }
  
          @Override
          public String toString() {
              // using ordinals to avoid javac synthetic inner class
              switch (ordinal()) {
                  case 0: return "ParseCaseSensitive(true)";
                  case 1: return "ParseCaseSensitive(false)";
                  case 2: return "ParseStrict(true)";
                  case 3: return "ParseStrict(false)";
              }
              throw new IllegalStateException("Unreachable");
          }
      }
  
      //-----------------------------------------------------------------------
      /**
       * Defaults a value into the parse if not currently present.
       */
      static class DefaultValueParser implements DateTimePrinterParser {
          private final TemporalField field;
          private final long value;
  
          DefaultValueParser(TemporalField field, long value) {
              this.field = field;
              this.value = value;
          }
  
          public boolean format(DateTimePrintContext context, StringBuilder buf) {
              return true;
          }
  
          public int parse(DateTimeParseContext context, CharSequence text, int position) {
              if (context.getParsed(field) == null) {
                  context.setParsedField(field, value, position, position);
              }
              return position;
          }
      }
  
      //-----------------------------------------------------------------------
      /**
       * Prints or parses a character literal.
       */
      static final class CharLiteralPrinterParser implements DateTimePrinterParser {
          private final char literal;
  
          CharLiteralPrinterParser(char literal) {
              this.literal = literal;
          }
  
          @Override
          public boolean format(DateTimePrintContext context, StringBuilder buf) {
              buf.append(literal);
              return true;
          }
  
          @Override
          public int parse(DateTimeParseContext context, CharSequence text, int position) {
              int length = text.length();
              if (position == length) {
                  return ~position;
              }
              char ch = text.charAt(position);
              if (ch != literal) {
                  if (context.isCaseSensitive() ||
                          (Character.toUpperCase(ch) != Character.toUpperCase(literal) &&
                           Character.toLowerCase(ch) != Character.toLowerCase(literal))) {
                      return ~position;
                  }
              }
              return position + 1;
          }
  
          @Override
          public String toString() {
              if (literal == '\'') {
                  return "''";
              }
              return "'" + literal + "'";
          }
      }
  
      //-----------------------------------------------------------------------
      /**
       * Prints or parses a string literal.
       */
      static final class StringLiteralPrinterParser implements DateTimePrinterParser {
          private final String literal;
  
          StringLiteralPrinterParser(String literal) {
              this.literal = literal;  // validated by caller
          }
  
          @Override
          public boolean format(DateTimePrintContext context, StringBuilder buf) {
              buf.append(literal);
              return true;
          }
  
          @Override
          public int parse(DateTimeParseContext context, CharSequence text, int position) {
              int length = text.length();
              if (position > length || position < 0) {
                  throw new IndexOutOfBoundsException();
              }
              if (context.subSequenceEquals(text, position, literal, 0, literal.length()) == false) {
                  return ~position;
              }
              return position + literal.length();
          }
  
          @Override
          public String toString() {
              String converted = literal.replace("'", "''");
              return "'" + converted + "'";
          }
      }
  
      //-----------------------------------------------------------------------
      /**
       * Prints and parses a numeric date-time field with optional padding.
       */
      static class NumberPrinterParser implements DateTimePrinterParser {
  
          /**
           * Array of 10 to the power of n.
           */
          static final long[] EXCEED_POINTS = new long[] {
              0L,
              10L,
              100L,
              1000L,
              10000L,
              100000L,
              1000000L,
              10000000L,
              100000000L,
              1000000000L,
              10000000000L,
          };
  
          final TemporalField field;
          final int minWidth;
          final int maxWidth;
          private final SignStyle signStyle;
          final int subsequentWidth;
  
          /**
           * Constructor.
           *
           * @param field  the field to format, not null
           * @param minWidth  the minimum field width, from 1 to 19
           * @param maxWidth  the maximum field width, from minWidth to 19
           * @param signStyle  the positive/negative sign style, not null
           */
          NumberPrinterParser(TemporalField field, int minWidth, int maxWidth, SignStyle signStyle) {
              // validated by caller
              this.field = field;
              this.minWidth = minWidth;
              this.maxWidth = maxWidth;
              this.signStyle = signStyle;
              this.subsequentWidth = 0;
          }
  
          /**
           * Constructor.
           *
           * @param field  the field to format, not null
           * @param minWidth  the minimum field width, from 1 to 19
           * @param maxWidth  the maximum field width, from minWidth to 19
           * @param signStyle  the positive/negative sign style, not null
           * @param subsequentWidth  the width of subsequent non-negative numbers, 0 or greater,
           *  -1 if fixed width due to active adjacent parsing
           */
          protected NumberPrinterParser(TemporalField field, int minWidth, int maxWidth, SignStyle signStyle, int subsequentWidth) {
              // validated by caller
              this.field = field;
              this.minWidth = minWidth;
              this.maxWidth = maxWidth;
              this.signStyle = signStyle;
              this.subsequentWidth = subsequentWidth;
          }
  
          /**
           * Returns a new instance with fixed width flag set.
           *
           * @return a new updated printer-parser, not null
           */
          NumberPrinterParser withFixedWidth() {
              if (subsequentWidth == -1) {
                  return this;
              }
              return new NumberPrinterParser(field, minWidth, maxWidth, signStyle, -1);
          }
  
          /**
           * Returns a new instance with an updated subsequent width.
           *
           * @param subsequentWidth  the width of subsequent non-negative numbers, 0 or greater
           * @return a new updated printer-parser, not null
           */
          NumberPrinterParser withSubsequentWidth(int subsequentWidth) {
              return new NumberPrinterParser(field, minWidth, maxWidth, signStyle, this.subsequentWidth + subsequentWidth);
          }
  
          @Override
          public boolean format(DateTimePrintContext context, StringBuilder buf) {
              Long valueLong = context.getValue(field);
              if (valueLong == null) {
                  return false;
              }
              long value = getValue(context, valueLong);
              DecimalStyle decimalStyle = context.getDecimalStyle();
              String str = (value == Long.MIN_VALUE ? "9223372036854775808" : Long.toString(Math.abs(value)));
              if (str.length() > maxWidth) {
                  throw new DateTimeException("Field " + field +
                      " cannot be printed as the value " + value +
                      " exceeds the maximum print width of " + maxWidth);
              }
              str = decimalStyle.convertNumberToI18N(str);
  
              if (value >= 0) {
                  switch (signStyle) {
                      case EXCEEDS_PAD:
                          if (minWidth < 19 && value >= EXCEED_POINTS[minWidth]) {
                              buf.append(decimalStyle.getPositiveSign());
                          }
                          break;
                      case ALWAYS:
                          buf.append(decimalStyle.getPositiveSign());
                          break;
                  }
              } else {
                  switch (signStyle) {
                      case NORMAL:
                      case EXCEEDS_PAD:
                      case ALWAYS:
                          buf.append(decimalStyle.getNegativeSign());
                          break;
                      case NOT_NEGATIVE:
                          throw new DateTimeException("Field " + field +
                              " cannot be printed as the value " + value +
                              " cannot be negative according to the SignStyle");
                  }
              }
              for (int i = 0; i < minWidth - str.length(); i++) {
                  buf.append(decimalStyle.getZeroDigit());
              }
              buf.append(str);
              return true;
          }
  
          /**
           * Gets the value to output.
           *
           * @param context  the context
           * @param value  the value of the field, not null
           * @return the value
           */
          long getValue(DateTimePrintContext context, long value) {
              return value;
          }
  
          /**
           * For NumberPrinterParser, the width is fixed depending on the
           * minWidth, maxWidth, signStyle and whether subsequent fields are fixed.
           * @param context the context
           * @return true if the field is fixed width
           * @see DateTimeFormatterBuilder#appendValue(TemporalField, int)
           */
          boolean isFixedWidth(DateTimeParseContext context) {
              return subsequentWidth == -1 ||
                  (subsequentWidth > 0 && minWidth == maxWidth && signStyle == SignStyle.NOT_NEGATIVE);
          }
  
          @Override
          public int parse(DateTimeParseContext context, CharSequence text, int position) {
              int length = text.length();
              if (position == length) {
                  return ~position;
              }
              char sign = text.charAt(position);  // IOOBE if invalid position
              boolean negative = false;
              boolean positive = false;
              if (sign == context.getDecimalStyle().getPositiveSign()) {
                  if (signStyle.parse(true, context.isStrict(), minWidth == maxWidth) == false) {
                      return ~position;
                  }
                  positive = true;
                  position++;
              } else if (sign == context.getDecimalStyle().getNegativeSign()) {
                  if (signStyle.parse(false, context.isStrict(), minWidth == maxWidth) == false) {
                      return ~position;
                  }
                  negative = true;
                  position++;
              } else {
                  if (signStyle == SignStyle.ALWAYS && context.isStrict()) {
                      return ~position;
                  }
              }
              int effMinWidth = (context.isStrict() || isFixedWidth(context) ? minWidth : 1);
              int minEndPos = position + effMinWidth;
              if (minEndPos > length) {
                  return ~position;
              }
              int effMaxWidth = (context.isStrict() || isFixedWidth(context) ? maxWidth : 9) + Math.max(subsequentWidth, 0);
              long total = 0;
              BigInteger totalBig = null;
              int pos = position;
              for (int pass = 0; pass < 2; pass++) {
                  int maxEndPos = Math.min(pos + effMaxWidth, length);
                  while (pos < maxEndPos) {
                      char ch = text.charAt(pos++);
                      int digit = context.getDecimalStyle().convertToDigit(ch);
                      if (digit < 0) {
                          pos--;
                          if (pos < minEndPos) {
                              return ~position;  // need at least min width digits
                          }
                          break;
                      }
                      if ((pos - position) > 18) {
                          if (totalBig == null) {
                              totalBig = BigInteger.valueOf(total);
                          }
                          totalBig = totalBig.multiply(BigInteger.TEN).add(BigInteger.valueOf(digit));
                      } else {
                          total = total * 10 + digit;
                      }
                  }
                  if (subsequentWidth > 0 && pass == 0) {
                      // re-parse now we know the correct width
                      int parseLen = pos - position;
                      effMaxWidth = Math.max(effMinWidth, parseLen - subsequentWidth);
                      pos = position;
                      total = 0;
                      totalBig = null;
                  } else {
                      break;
                  }
              }
              if (negative) {
                  if (totalBig != null) {
                      if (totalBig.equals(BigInteger.ZERO) && context.isStrict()) {
                          return ~(position - 1);  // minus zero not allowed
                      }
                      totalBig = totalBig.negate();
                  } else {
                      if (total == 0 && context.isStrict()) {
                          return ~(position - 1);  // minus zero not allowed
                      }
                      total = -total;
                  }
              } else if (signStyle == SignStyle.EXCEEDS_PAD && context.isStrict()) {
                  int parseLen = pos - position;
                  if (positive) {
                      if (parseLen <= minWidth) {
                          return ~(position - 1);  // '+' only parsed if minWidth exceeded
                      }
                  } else {
                      if (parseLen > minWidth) {
                          return ~position;  // '+' must be parsed if minWidth exceeded
                      }
                  }
              }
              if (totalBig != null) {
                  if (totalBig.bitLength() > 63) {
                      // overflow, parse 1 less digit
                      totalBig = totalBig.divide(BigInteger.TEN);
                      pos--;
                  }
                  return setValue(context, totalBig.longValue(), position, pos);
              }
              return setValue(context, total, position, pos);
          }
  
          /**
           * Stores the value.
           *
           * @param context  the context to store into, not null
           * @param value  the value
           * @param errorPos  the position of the field being parsed
           * @param successPos  the position after the field being parsed
           * @return the new position
           */
          int setValue(DateTimeParseContext context, long value, int errorPos, int successPos) {
              return context.setParsedField(field, value, errorPos, successPos);
          }
  
          @Override
          public String toString() {
              if (minWidth == 1 && maxWidth == 19 && signStyle == SignStyle.NORMAL) {
                  return "Value(" + field + ")";
              }
              if (minWidth == maxWidth && signStyle == SignStyle.NOT_NEGATIVE) {
                  return "Value(" + field + "," + minWidth + ")";
              }
              return "Value(" + field + "," + minWidth + "," + maxWidth + "," + signStyle + ")";
          }
      }
  
      //-----------------------------------------------------------------------
      /**
       * Prints and parses a reduced numeric date-time field.
       */
      static final class ReducedPrinterParser extends NumberPrinterParser {
          /**
           * The base date for reduced value parsing.
           */
          static final LocalDate BASE_DATE = LocalDate.of(2000, 1, 1);
  
          private final int baseValue;
          private final ChronoLocalDate baseDate;
  
          /**
           * Constructor.
           *
           * @param field  the field to format, validated not null
           * @param minWidth  the minimum field width, from 1 to 10
           * @param maxWidth  the maximum field width, from 1 to 10
           * @param baseValue  the base value
           * @param baseDate  the base date
           */
          ReducedPrinterParser(TemporalField field, int minWidth, int maxWidth,
                  int baseValue, ChronoLocalDate baseDate) {
              this(field, minWidth, maxWidth, baseValue, baseDate, 0);
              if (minWidth < 1 || minWidth > 10) {
                  throw new IllegalArgumentException("The minWidth must be from 1 to 10 inclusive but was " + minWidth);
              }
              if (maxWidth < 1 || maxWidth > 10) {
                  throw new IllegalArgumentException("The maxWidth must be from 1 to 10 inclusive but was " + minWidth);
              }
              if (maxWidth < minWidth) {
                  throw new IllegalArgumentException("Maximum width must exceed or equal the minimum width but " +
                          maxWidth + " < " + minWidth);
              }
              if (baseDate == null) {
                  if (field.range().isValidValue(baseValue) == false) {
                      throw new IllegalArgumentException("The base value must be within the range of the field");
                  }
                  if ((((long) baseValue) + EXCEED_POINTS[maxWidth]) > Integer.MAX_VALUE) {
                      throw new DateTimeException("Unable to add printer-parser as the range exceeds the capacity of an int");
                  }
              }
          }
  
          /**
           * Constructor.
           * The arguments have already been checked.
           *
           * @param field  the field to format, validated not null
           * @param minWidth  the minimum field width, from 1 to 10
           * @param maxWidth  the maximum field width, from 1 to 10
           * @param baseValue  the base value
           * @param baseDate  the base date
           * @param subsequentWidth the subsequentWidth for this instance
           */
          private ReducedPrinterParser(TemporalField field, int minWidth, int maxWidth,
                  int baseValue, ChronoLocalDate baseDate, int subsequentWidth) {
              super(field, minWidth, maxWidth, SignStyle.NOT_NEGATIVE, subsequentWidth);
              this.baseValue = baseValue;
              this.baseDate = baseDate;
          }
  
          @Override
          long getValue(DateTimePrintContext context, long value) {
              long absValue = Math.abs(value);
              int baseValue = this.baseValue;
              if (baseDate != null) {
                  Chronology chrono = Chronology.from(context.getTemporal());
                  baseValue = chrono.date(baseDate).get(field);
              }
              if (value >= baseValue && value < baseValue + EXCEED_POINTS[minWidth]) {
                  // Use the reduced value if it fits in minWidth
                  return absValue % EXCEED_POINTS[minWidth];
              }
              // Otherwise truncate to fit in maxWidth
              return absValue % EXCEED_POINTS[maxWidth];
          }
  
          @Override
          int setValue(DateTimeParseContext context, long value, int errorPos, int successPos) {
              int baseValue = this.baseValue;
              if (baseDate != null) {
                  Chronology chrono = context.getEffectiveChronology();
                  baseValue = chrono.date(baseDate).get(field);
  
                  // In case the Chronology is changed later, add a callback when/if it changes
                  final long initialValue = value;
                  context.addChronoChangedListener(
                          (_unused) ->  {
                              /* Repeat the set of the field using the current Chronology
                               * The success/error position is ignored because the value is
                               * intentionally being overwritten.
                               */
                              setValue(context, initialValue, errorPos, successPos);
                          });
              }
              int parseLen = successPos - errorPos;
              if (parseLen == minWidth && value >= 0) {
                  long range = EXCEED_POINTS[minWidth];
                  long lastPart = baseValue % range;
                  long basePart = baseValue - lastPart;
                  if (baseValue > 0) {
                      value = basePart + value;
                  } else {
                      value = basePart - value;
                  }
                  if (value < baseValue) {
                      value += range;
                  }
              }
              return context.setParsedField(field, value, errorPos, successPos);
          }
  
          /**
           * Returns a new instance with fixed width flag set.
           *
           * @return a new updated printer-parser, not null
           */
          @Override
          ReducedPrinterParser withFixedWidth() {
              if (subsequentWidth == -1) {
                  return this;
              }
              return new ReducedPrinterParser(field, minWidth, maxWidth, baseValue, baseDate, -1);
          }
  
          /**
           * Returns a new instance with an updated subsequent width.
           *
           * @param subsequentWidth  the width of subsequent non-negative numbers, 0 or greater
           * @return a new updated printer-parser, not null
           */
          @Override
          ReducedPrinterParser withSubsequentWidth(int subsequentWidth) {
              return new ReducedPrinterParser(field, minWidth, maxWidth, baseValue, baseDate,
                      this.subsequentWidth + subsequentWidth);
          }
  
          /**
           * For a ReducedPrinterParser, fixed width is false if the mode is strict,
           * otherwise it is set as for NumberPrinterParser.
           * @param context the context
           * @return if the field is fixed width
           * @see DateTimeFormatterBuilder#appendValueReduced(TemporalField, int, int, int)
           */
          @Override
          boolean isFixedWidth(DateTimeParseContext context) {
             if (context.isStrict() == false) {
                 return false;
             }
             return super.isFixedWidth(context);
          }
  
          @Override
          public String toString() {
              return "ReducedValue(" + field + "," + minWidth + "," + maxWidth + "," + (baseDate != null ? baseDate : baseValue) + ")";
          }
      }
  
      //-----------------------------------------------------------------------
      /**
       * Prints and parses a numeric date-time field with optional padding.
       */
      static final class FractionPrinterParser implements DateTimePrinterParser {
          private final TemporalField field;
          private final int minWidth;
          private final int maxWidth;
          private final boolean decimalPoint;
  
          /**
           * Constructor.
           *
           * @param field  the field to output, not null
           * @param minWidth  the minimum width to output, from 0 to 9
           * @param maxWidth  the maximum width to output, from 0 to 9
           * @param decimalPoint  whether to output the localized decimal point symbol
           */
          FractionPrinterParser(TemporalField field, int minWidth, int maxWidth, boolean decimalPoint) {
              Objects.requireNonNull(field, "field");
              if (field.range().isFixed() == false) {
                  throw new IllegalArgumentException("Field must have a fixed set of values: " + field);
              }
              if (minWidth < 0 || minWidth > 9) {
                  throw new IllegalArgumentException("Minimum width must be from 0 to 9 inclusive but was " + minWidth);
              }
              if (maxWidth < 1 || maxWidth > 9) {
                  throw new IllegalArgumentException("Maximum width must be from 1 to 9 inclusive but was " + maxWidth);
              }
              if (maxWidth < minWidth) {
                  throw new IllegalArgumentException("Maximum width must exceed or equal the minimum width but " +
                          maxWidth + " < " + minWidth);
              }
              this.field = field;
              this.minWidth = minWidth;
              this.maxWidth = maxWidth;
              this.decimalPoint = decimalPoint;
          }
  
          @Override
          public boolean format(DateTimePrintContext context, StringBuilder buf) {
              Long value = context.getValue(field);
              if (value == null) {
                  return false;
              }
              DecimalStyle decimalStyle = context.getDecimalStyle();
              BigDecimal fraction = convertToFraction(value);
              if (fraction.scale() == 0) {  // scale is zero if value is zero
                  if (minWidth > 0) {
                      if (decimalPoint) {
                          buf.append(decimalStyle.getDecimalSeparator());
                      }
                      for (int i = 0; i < minWidth; i++) {
                          buf.append(decimalStyle.getZeroDigit());
                      }
                  }
              } else {
                  int outputScale = Math.min(Math.max(fraction.scale(), minWidth), maxWidth);
                  fraction = fraction.setScale(outputScale, RoundingMode.FLOOR);
                  String str = fraction.toPlainString().substring(2);
                  str = decimalStyle.convertNumberToI18N(str);
                  if (decimalPoint) {
                      buf.append(decimalStyle.getDecimalSeparator());
                  }
                  buf.append(str);
              }
              return true;
          }
  
          @Override
          public int parse(DateTimeParseContext context, CharSequence text, int position) {
              int effectiveMin = (context.isStrict() ? minWidth : 0);
              int effectiveMax = (context.isStrict() ? maxWidth : 9);
              int length = text.length();
              if (position == length) {
                  // valid if whole field is optional, invalid if minimum width
                  return (effectiveMin > 0 ? ~position : position);
              }
              if (decimalPoint) {
                  if (text.charAt(position) != context.getDecimalStyle().getDecimalSeparator()) {
                      // valid if whole field is optional, invalid if minimum width
                      return (effectiveMin > 0 ? ~position : position);
                  }
                  position++;
              }
              int minEndPos = position + effectiveMin;
              if (minEndPos > length) {
                  return ~position;  // need at least min width digits
              }
              int maxEndPos = Math.min(position + effectiveMax, length);
              int total = 0;  // can use int because we are only parsing up to 9 digits
              int pos = position;
              while (pos < maxEndPos) {
                  char ch = text.charAt(pos++);
                  int digit = context.getDecimalStyle().convertToDigit(ch);
                  if (digit < 0) {
                      if (pos < minEndPos) {
                          return ~position;  // need at least min width digits
                      }
                      pos--;
                      break;
                  }
                  total = total * 10 + digit;
              }
              BigDecimal fraction = new BigDecimal(total).movePointLeft(pos - position);
              long value = convertFromFraction(fraction);
              return context.setParsedField(field, value, position, pos);
          }
  
          /**
           * Converts a value for this field to a fraction between 0 and 1.
           * <p>
           * The fractional value is between 0 (inclusive) and 1 (exclusive).
           * It can only be returned if the {@link TemporalField#range() value range} is fixed.
           * The fraction is obtained by calculation from the field range using 9 decimal
           * places and a rounding mode of {@link RoundingMode#FLOOR FLOOR}.
           * The calculation is inaccurate if the values do not run continuously from smallest to largest.
           * <p>
           * For example, the second-of-minute value of 15 would be returned as 0.25,
           * assuming the standard definition of 60 seconds in a minute.
           *
           * @param value  the value to convert, must be valid for this rule
           * @return the value as a fraction within the range, from 0 to 1, not null
           * @throws DateTimeException if the value cannot be converted to a fraction
           */
          private BigDecimal convertToFraction(long value) {
              ValueRange range = field.range();
              range.checkValidValue(value, field);
              BigDecimal minBD = BigDecimal.valueOf(range.getMinimum());
              BigDecimal rangeBD = BigDecimal.valueOf(range.getMaximum()).subtract(minBD).add(BigDecimal.ONE);
              BigDecimal valueBD = BigDecimal.valueOf(value).subtract(minBD);
              BigDecimal fraction = valueBD.divide(rangeBD, 9, RoundingMode.FLOOR);
              // stripTrailingZeros bug
              return fraction.compareTo(BigDecimal.ZERO) == 0 ? BigDecimal.ZERO : fraction.stripTrailingZeros();
          }
  
          /**
           * Converts a fraction from 0 to 1 for this field to a value.
           * <p>
           * The fractional value must be between 0 (inclusive) and 1 (exclusive).
           * It can only be returned if the {@link TemporalField#range() value range} is fixed.
           * The value is obtained by calculation from the field range and a rounding
           * mode of {@link RoundingMode#FLOOR FLOOR}.
           * The calculation is inaccurate if the values do not run continuously from smallest to largest.
           * <p>
           * For example, the fractional second-of-minute of 0.25 would be converted to 15,
           * assuming the standard definition of 60 seconds in a minute.
           *
           * @param fraction  the fraction to convert, not null
           * @return the value of the field, valid for this rule
           * @throws DateTimeException if the value cannot be converted
           */
          private long convertFromFraction(BigDecimal fraction) {
              ValueRange range = field.range();
              BigDecimal minBD = BigDecimal.valueOf(range.getMinimum());
              BigDecimal rangeBD = BigDecimal.valueOf(range.getMaximum()).subtract(minBD).add(BigDecimal.ONE);
              BigDecimal valueBD = fraction.multiply(rangeBD).setScale(0, RoundingMode.FLOOR).add(minBD);
              return valueBD.longValueExact();
          }
  
          @Override
          public String toString() {
              String decimal = (decimalPoint ? ",DecimalPoint" : "");
              return "Fraction(" + field + "," + minWidth + "," + maxWidth + decimal + ")";
          }
      }
  
      //-----------------------------------------------------------------------
      /**
       * Prints or parses field text.
       */
      static final class TextPrinterParser implements DateTimePrinterParser {
          private final TemporalField field;
          private final TextStyle textStyle;
          private final DateTimeTextProvider provider;
          /**
           * The cached number printer parser.
           * Immutable and volatile, so no synchronization needed.
           */
          private volatile NumberPrinterParser numberPrinterParser;
  
          /**
           * Constructor.
           *
           * @param field  the field to output, not null
           * @param textStyle  the text style, not null
           * @param provider  the text provider, not null
           */
          TextPrinterParser(TemporalField field, TextStyle textStyle, DateTimeTextProvider provider) {
              // validated by caller
              this.field = field;
              this.textStyle = textStyle;
              this.provider = provider;
          }
  
          @Override
          public boolean format(DateTimePrintContext context, StringBuilder buf) {
              Long value = context.getValue(field);
              if (value == null) {
                  return false;
              }
              String text;
              Chronology chrono = context.getTemporal().query(TemporalQueries.chronology());
              if (chrono == null || chrono == IsoChronology.INSTANCE) {
                  text = provider.getText(field, value, textStyle, context.getLocale());
              } else {
                  text = provider.getText(chrono, field, value, textStyle, context.getLocale());
              }
              if (text == null) {
                  return numberPrinterParser().format(context, buf);
              }
              buf.append(text);
              return true;
          }
  
          @Override
          public int parse(DateTimeParseContext context, CharSequence parseText, int position) {
              int length = parseText.length();
              if (position < 0 || position > length) {
                  throw new IndexOutOfBoundsException();
              }
              TextStyle style = (context.isStrict() ? textStyle : null);
              Chronology chrono = context.getEffectiveChronology();
              Iterator<Entry<String, Long>> it;
              if (chrono == null || chrono == IsoChronology.INSTANCE) {
                  it = provider.getTextIterator(field, style, context.getLocale());
              } else {
                  it = provider.getTextIterator(chrono, field, style, context.getLocale());
              }
              if (it != null) {
                  while (it.hasNext()) {
                      Entry<String, Long> entry = it.next();
                      String itText = entry.getKey();
                      if (context.subSequenceEquals(itText, 0, parseText, position, itText.length())) {
                          return context.setParsedField(field, entry.getValue(), position, position + itText.length());
                      }
                  }
                  if (context.isStrict()) {
                      return ~position;
                  }
              }
              return numberPrinterParser().parse(context, parseText, position);
          }
  
          /**
           * Create and cache a number printer parser.
           * @return the number printer parser for this field, not null
           */
          private NumberPrinterParser numberPrinterParser() {
              if (numberPrinterParser == null) {
                  numberPrinterParser = new NumberPrinterParser(field, 1, 19, SignStyle.NORMAL);
              }
              return numberPrinterParser;
          }
  
          @Override
          public String toString() {
              if (textStyle == TextStyle.FULL) {
                  return "Text(" + field + ")";
              }
              return "Text(" + field + "," + textStyle + ")";
          }
      }
  
      //-----------------------------------------------------------------------
      /**
       * Prints or parses an ISO-8601 instant.
       */
      static final class InstantPrinterParser implements DateTimePrinterParser {
          // days in a 400 year cycle = 146097
          // days in a 10,000 year cycle = 146097 * 25
          // seconds per day = 86400
          private static final long SECONDS_PER_10000_YEARS = 146097L * 25L * 86400L;
          private static final long SECONDS_0000_TO_1970 = ((146097L * 5L) - (30L * 365L + 7L)) * 86400L;
          private final int fractionalDigits;
  
          InstantPrinterParser(int fractionalDigits) {
              this.fractionalDigits = fractionalDigits;
          }
  
          @Override
          public boolean format(DateTimePrintContext context, StringBuilder buf) {
              // use INSTANT_SECONDS, thus this code is not bound by Instant.MAX
              Long inSecs = context.getValue(INSTANT_SECONDS);
              Long inNanos = null;
              if (context.getTemporal().isSupported(NANO_OF_SECOND)) {
                  inNanos = context.getTemporal().getLong(NANO_OF_SECOND);
              }
              if (inSecs == null) {
                  return false;
              }
              long inSec = inSecs;
              int inNano = NANO_OF_SECOND.checkValidIntValue(inNanos != null ? inNanos : 0);
              // format mostly using LocalDateTime.toString
              if (inSec >= -SECONDS_0000_TO_1970) {
                  // current era
                  long zeroSecs = inSec - SECONDS_PER_10000_YEARS + SECONDS_0000_TO_1970;
                  long hi = Math.floorDiv(zeroSecs, SECONDS_PER_10000_YEARS) + 1;
                  long lo = Math.floorMod(zeroSecs, SECONDS_PER_10000_YEARS);
                  LocalDateTime ldt = LocalDateTime.ofEpochSecond(lo - SECONDS_0000_TO_1970, 0, ZoneOffset.UTC);
                  if (hi > 0) {
                      buf.append('+').append(hi);
                  }
                  buf.append(ldt);
                  if (ldt.getSecond() == 0) {
                      buf.append(":00");
                  }
              } else {
                  // before current era
                  long zeroSecs = inSec + SECONDS_0000_TO_1970;
                  long hi = zeroSecs / SECONDS_PER_10000_YEARS;
                  long lo = zeroSecs % SECONDS_PER_10000_YEARS;
                  LocalDateTime ldt = LocalDateTime.ofEpochSecond(lo - SECONDS_0000_TO_1970, 0, ZoneOffset.UTC);
                  int pos = buf.length();
                  buf.append(ldt);
                  if (ldt.getSecond() == 0) {
                      buf.append(":00");
                  }
                  if (hi < 0) {
                      if (ldt.getYear() == -10_000) {
                          buf.replace(pos, pos + 2, Long.toString(hi - 1));
                      } else if (lo == 0) {
                          buf.insert(pos, hi);
                      } else {
                          buf.insert(pos + 1, Math.abs(hi));
                      }
                  }
              }
              // add fraction
              if ((fractionalDigits < 0 && inNano > 0) || fractionalDigits > 0) {
                  buf.append('.');
                  int div = 100_000_000;
                  for (int i = 0; ((fractionalDigits == -1 && inNano > 0) ||
                                      (fractionalDigits == -2 && (inNano > 0 || (i % 3) != 0)) ||
                                      i < fractionalDigits); i++) {
                      int digit = inNano / div;
                      buf.append((char) (digit + '0'));
                      inNano = inNano - (digit * div);
                      div = div / 10;
                  }
              }
              buf.append('Z');
              return true;
          }
  
          @Override
          public int parse(DateTimeParseContext context, CharSequence text, int position) {
              // new context to avoid overwriting fields like year/month/day
              int minDigits = (fractionalDigits < 0 ? 0 : fractionalDigits);
              int maxDigits = (fractionalDigits < 0 ? 9 : fractionalDigits);
              CompositePrinterParser parser = new DateTimeFormatterBuilder()
                      .append(DateTimeFormatter.ISO_LOCAL_DATE).appendLiteral('T')
                      .appendValue(HOUR_OF_DAY, 2).appendLiteral(':')
                      .appendValue(MINUTE_OF_HOUR, 2).appendLiteral(':')
                      .appendValue(SECOND_OF_MINUTE, 2)
                      .appendFraction(NANO_OF_SECOND, minDigits, maxDigits, true)
                      .appendLiteral('Z')
                      .toFormatter().toPrinterParser(false);
              DateTimeParseContext newContext = context.copy();
              int pos = parser.parse(newContext, text, position);
              if (pos < 0) {
                  return pos;
              }
              // parser restricts most fields to 2 digits, so definitely int
              // correctly parsed nano is also guaranteed to be valid
              long yearParsed = newContext.getParsed(YEAR);
              int month = newContext.getParsed(MONTH_OF_YEAR).intValue();
              int day = newContext.getParsed(DAY_OF_MONTH).intValue();
              int hour = newContext.getParsed(HOUR_OF_DAY).intValue();
              int min = newContext.getParsed(MINUTE_OF_HOUR).intValue();
              Long secVal = newContext.getParsed(SECOND_OF_MINUTE);
              Long nanoVal = newContext.getParsed(NANO_OF_SECOND);
              int sec = (secVal != null ? secVal.intValue() : 0);
              int nano = (nanoVal != null ? nanoVal.intValue() : 0);
              int days = 0;
              if (hour == 24 && min == 0 && sec == 0 && nano == 0) {
                  hour = 0;
                  days = 1;
              } else if (hour == 23 && min == 59 && sec == 60) {
                  context.setParsedLeapSecond();
                  sec = 59;
              }
              int year = (int) yearParsed % 10_000;
              long instantSecs;
              try {
                  LocalDateTime ldt = LocalDateTime.of(year, month, day, hour, min, sec, 0).plusDays(days);
                  instantSecs = ldt.toEpochSecond(ZoneOffset.UTC);
                  instantSecs += Math.multiplyExact(yearParsed / 10_000L, SECONDS_PER_10000_YEARS);
              } catch (RuntimeException ex) {
                  return ~position;
              }
              int successPos = pos;
              successPos = context.setParsedField(INSTANT_SECONDS, instantSecs, position, successPos);
              return context.setParsedField(NANO_OF_SECOND, nano, position, successPos);
          }
  
          @Override
          public String toString() {
              return "Instant()";
          }
      }
  
      //-----------------------------------------------------------------------
      /**
       * Prints or parses an offset ID.
       */
      static final class OffsetIdPrinterParser implements DateTimePrinterParser {
          static final String[] PATTERNS = new String[] {
              "+HH", "+HHmm", "+HH:mm", "+HHMM", "+HH:MM", "+HHMMss", "+HH:MM:ss", "+HHMMSS", "+HH:MM:SS",
          };  // order used in pattern builder
          static final OffsetIdPrinterParser INSTANCE_ID_Z = new OffsetIdPrinterParser("+HH:MM:ss", "Z");
          static final OffsetIdPrinterParser INSTANCE_ID_ZERO = new OffsetIdPrinterParser("+HH:MM:ss", "0");
  
          private final String noOffsetText;
          private final int type;
  
          /**
           * Constructor.
           *
           * @param pattern  the pattern
           * @param noOffsetText  the text to use for UTC, not null
           */
          OffsetIdPrinterParser(String pattern, String noOffsetText) {
              Objects.requireNonNull(pattern, "pattern");
              Objects.requireNonNull(noOffsetText, "noOffsetText");
              this.type = checkPattern(pattern);
              this.noOffsetText = noOffsetText;
          }
  
          private int checkPattern(String pattern) {
              for (int i = 0; i < PATTERNS.length; i++) {
                  if (PATTERNS[i].equals(pattern)) {
                      return i;
                  }
              }
              throw new IllegalArgumentException("Invalid zone offset pattern: " + pattern);
          }
  
          @Override
          public boolean format(DateTimePrintContext context, StringBuilder buf) {
              Long offsetSecs = context.getValue(OFFSET_SECONDS);
              if (offsetSecs == null) {
                  return false;
              }
              int totalSecs = Math.toIntExact(offsetSecs);
              if (totalSecs == 0) {
                  buf.append(noOffsetText);
              } else {
                  int absHours = Math.abs((totalSecs / 3600) % 100);  // anything larger than 99 silently dropped
                  int absMinutes = Math.abs((totalSecs / 60) % 60);
                  int absSeconds = Math.abs(totalSecs % 60);
                  int bufPos = buf.length();
                  int output = absHours;
                  buf.append(totalSecs < 0 ? "-" : "+")
                      .append((char) (absHours / 10 + '0')).append((char) (absHours % 10 + '0'));
                  if (type >= 3 || (type >= 1 && absMinutes > 0)) {
                      buf.append((type % 2) == 0 ? ":" : "")
                          .append((char) (absMinutes / 10 + '0')).append((char) (absMinutes % 10 + '0'));
                      output += absMinutes;
                      if (type >= 7 || (type >= 5 && absSeconds > 0)) {
                          buf.append((type % 2) == 0 ? ":" : "")
                              .append((char) (absSeconds / 10 + '0')).append((char) (absSeconds % 10 + '0'));
                          output += absSeconds;
                      }
                  }
                  if (output == 0) {
                      buf.setLength(bufPos);
                      buf.append(noOffsetText);
                  }
              }
              return true;
          }
  
          @Override
          public int parse(DateTimeParseContext context, CharSequence text, int position) {
              int length = text.length();
              int noOffsetLen = noOffsetText.length();
              if (noOffsetLen == 0) {
                  if (position == length) {
                      return context.setParsedField(OFFSET_SECONDS, 0, position, position);
                  }
              } else {
                  if (position == length) {
                      return ~position;
                  }
                  if (context.subSequenceEquals(text, position, noOffsetText, 0, noOffsetLen)) {
                      return context.setParsedField(OFFSET_SECONDS, 0, position, position + noOffsetLen);
                  }
              }
  
              // parse normal plus/minus offset
              char sign = text.charAt(position);  // IOOBE if invalid position
              if (sign == '+' || sign == '-') {
                  // starts
                  int negative = (sign == '-' ? -1 : 1);
                  int[] array = new int[4];
                  array[0] = position + 1;
                  if ((parseNumber(array, 1, text, true) ||
                          parseNumber(array, 2, text, type >=3) ||
                          parseNumber(array, 3, text, false)) == false) {
                      // success
                      long offsetSecs = negative * (array[1] * 3600L + array[2] * 60L + array[3]);
                      return context.setParsedField(OFFSET_SECONDS, offsetSecs, position, array[0]);
                  }
              }
              // handle special case of empty no offset text
              if (noOffsetLen == 0) {
                  return context.setParsedField(OFFSET_SECONDS, 0, position, position + noOffsetLen);
              }
              return ~position;
          }
  
          /**
           * Parse a two digit zero-prefixed number.
           *
           * @param array  the array of parsed data, 0=pos,1=hours,2=mins,3=secs, not null
           * @param arrayIndex  the index to parse the value into
           * @param parseText  the offset ID, not null
           * @param required  whether this number is required
           * @return true if an error occurred
           */
          private boolean parseNumber(int[] array, int arrayIndex, CharSequence parseText, boolean required) {
              if ((type + 3) / 2 < arrayIndex) {
                  return false;  // ignore seconds/minutes
              }
              int pos = array[0];
              if ((type % 2) == 0 && arrayIndex > 1) {
                  if (pos + 1 > parseText.length() || parseText.charAt(pos) != ':') {
                      return required;
                  }
                  pos++;
              }
              if (pos + 2 > parseText.length()) {
                  return required;
              }
              char ch1 = parseText.charAt(pos++);
              char ch2 = parseText.charAt(pos++);
              if (ch1 < '0' || ch1 > '9' || ch2 < '0' || ch2 > '9') {
                  return required;
              }
              int value = (ch1 - 48) * 10 + (ch2 - 48);
              if (value < 0 || value > 59) {
                  return required;
              }
              array[arrayIndex] = value;
              array[0] = pos;
              return false;
          }
  
          @Override
          public String toString() {
              String converted = noOffsetText.replace("'", "''");
              return "Offset(" + PATTERNS[type] + ",'" + converted + "')";
          }
      }
  
      //-----------------------------------------------------------------------
      /**
       * Prints or parses an offset ID.
       */
      static final class LocalizedOffsetIdPrinterParser implements DateTimePrinterParser {
          private final TextStyle style;
  
          /**
           * Constructor.
           *
           * @param style  the style, not null
           */
          LocalizedOffsetIdPrinterParser(TextStyle style) {
              this.style = style;
          }
  
          private static StringBuilder appendHMS(StringBuilder buf, int t) {
              return buf.append((char)(t / 10 + '0'))
                        .append((char)(t % 10 + '0'));
          }
  
          @Override
          public boolean format(DateTimePrintContext context, StringBuilder buf) {
              Long offsetSecs = context.getValue(OFFSET_SECONDS);
              if (offsetSecs == null) {
                  return false;
              }
              String gmtText = "GMT";  // TODO: get localized version of 'GMT'
              if (gmtText != null) {
                  buf.append(gmtText);
              }
              int totalSecs = Math.toIntExact(offsetSecs);
              if (totalSecs != 0) {
                  int absHours = Math.abs((totalSecs / 3600) % 100);  // anything larger than 99 silently dropped
                  int absMinutes = Math.abs((totalSecs / 60) % 60);
                  int absSeconds = Math.abs(totalSecs % 60);
                  buf.append(totalSecs < 0 ? "-" : "+");
                  if (style == TextStyle.FULL) {
                      appendHMS(buf, absHours);
                      buf.append(':');
                      appendHMS(buf, absMinutes);
                      if (absSeconds != 0) {
                         buf.append(':');
                         appendHMS(buf, absSeconds);
                      }
                  } else {
                      if (absHours >= 10) {
                          buf.append((char)(absHours / 10 + '0'));
                      }
                      buf.append((char)(absHours % 10 + '0'));
                      if (absMinutes != 0 || absSeconds != 0) {
                          buf.append(':');
                          appendHMS(buf, absMinutes);
                          if (absSeconds != 0) {
                              buf.append(':');
                              appendHMS(buf, absSeconds);
                          }
                      }
                  }
              }
              return true;
          }
  
          int getDigit(CharSequence text, int position) {
              char c = text.charAt(position);
              if (c < '0' || c > '9') {
                  return -1;
              }
              return c - '0';
          }
  
          @Override
          public int parse(DateTimeParseContext context, CharSequence text, int position) {
              int pos = position;
              int end = pos + text.length();
              String gmtText = "GMT";  // TODO: get localized version of 'GMT'
              if (gmtText != null) {
                  if (!context.subSequenceEquals(text, pos, gmtText, 0, gmtText.length())) {
                      return ~position;
                  }
                  pos += gmtText.length();
              }
              // parse normal plus/minus offset
              int negative = 0;
              if (pos == end) {
                  return context.setParsedField(OFFSET_SECONDS, 0, position, pos);
              }
              char sign = text.charAt(pos);  // IOOBE if invalid position
              if (sign == '+') {
                  negative = 1;
              } else if (sign == '-') {
                  negative = -1;
              } else {
                  return context.setParsedField(OFFSET_SECONDS, 0, position, pos);
              }
              pos++;
              int h = 0;
              int m = 0;
              int s = 0;
              if (style == TextStyle.FULL) {
                  int h1 = getDigit(text, pos++);
                  int h2 = getDigit(text, pos++);
                  if (h1 < 0 || h2 < 0 || text.charAt(pos++) != ':') {
                      return ~position;
                  }
                  h = h1 * 10 + h2;
                  int m1 = getDigit(text, pos++);
                  int m2 = getDigit(text, pos++);
                  if (m1 < 0 || m2 < 0) {
                      return ~position;
                  }
                  m = m1 * 10 + m2;
                  if (pos + 2 < end && text.charAt(pos) == ':') {
                      int s1 = getDigit(text, pos + 1);
                      int s2 = getDigit(text, pos + 2);
                      if (s1 >= 0 && s2 >= 0) {
                          s = s1 * 10 + s2;
                          pos += 3;
                      }
                  }
              } else {
                  h = getDigit(text, pos++);
                  if (h < 0) {
                      return ~position;
                  }
                  if (pos < end) {
                      int h2 = getDigit(text, pos);
                      if (h2 >=0) {
                          h = h * 10 + h2;
                          pos++;
                      }
                      if (pos + 2 < end && text.charAt(pos) == ':') {
                          if (pos + 2 < end && text.charAt(pos) == ':') {
                              int m1 = getDigit(text, pos + 1);
                              int m2 = getDigit(text, pos + 2);
                              if (m1 >= 0 && m2 >= 0) {
                                  m = m1 * 10 + m2;
                                  pos += 3;
                                  if (pos + 2 < end && text.charAt(pos) == ':') {
                                      int s1 = getDigit(text, pos + 1);
                                      int s2 = getDigit(text, pos + 2);
                                      if (s1 >= 0 && s2 >= 0) {
                                          s = s1 * 10 + s2;
                                          pos += 3;
                                     }
                                  }
                              }
                          }
                      }
                  }
              }
              long offsetSecs = negative * (h * 3600L + m * 60L + s);
              return context.setParsedField(OFFSET_SECONDS, offsetSecs, position, pos);
          }
  
          @Override
          public String toString() {
              return "LocalizedOffset(" + style + ")";
          }
      }
  
      //-----------------------------------------------------------------------
      /**
       * Prints or parses a zone ID.
       */
      static final class ZoneTextPrinterParser extends ZoneIdPrinterParser {
  
          /** The text style to output. */
          private final TextStyle textStyle;
  
          /** The preferred zoneid map */
          private Set<String> preferredZones;
  
          ZoneTextPrinterParser(TextStyle textStyle, Set<ZoneId> preferredZones) {
              super(TemporalQueries.zone(), "ZoneText(" + textStyle + ")");
              this.textStyle = Objects.requireNonNull(textStyle, "textStyle");
              if (preferredZones != null && preferredZones.size() != 0) {
                  this.preferredZones = new HashSet<>();
                  for (ZoneId id : preferredZones) {
                      this.preferredZones.add(id.getId());
                  }
              }
          }
  
          private static final int STD = 0;
          private static final int DST = 1;
          private static final int GENERIC = 2;
  
          // BEGIN Android-added: Lists of types used by getDisplayName().
          private static final TimeZoneNames.NameType[] TYPES = new TimeZoneNames.NameType[] {
                  TimeZoneNames.NameType.LONG_STANDARD,
                  TimeZoneNames.NameType.SHORT_STANDARD,
                  TimeZoneNames.NameType.LONG_DAYLIGHT,
                  TimeZoneNames.NameType.SHORT_DAYLIGHT,
                  TimeZoneNames.NameType.LONG_GENERIC,
                  TimeZoneNames.NameType.SHORT_GENERIC,
          };
  
          private static final TimeZoneNames.NameType[] FULL_TYPES = new TimeZoneNames.NameType[] {
                  TimeZoneNames.NameType.LONG_STANDARD,
                  TimeZoneNames.NameType.LONG_DAYLIGHT,
                  TimeZoneNames.NameType.LONG_GENERIC,
          };
  
          private static final TimeZoneNames.NameType[] SHORT_TYPES = new TimeZoneNames.NameType[] {
                  TimeZoneNames.NameType.SHORT_STANDARD,
                  TimeZoneNames.NameType.SHORT_DAYLIGHT,
                  TimeZoneNames.NameType.SHORT_GENERIC,
          };
          // END Android-added: Lists of types used by getDisplayName().
  
          private static final Map<String, SoftReference<Map<Locale, String[]>>> cache =
              new ConcurrentHashMap<>();
  
          private String getDisplayName(String id, int type, Locale locale) {
              if (textStyle == TextStyle.NARROW) {
                  return null;
              }
              String[] names;
              SoftReference<Map<Locale, String[]>> ref = cache.get(id);
              Map<Locale, String[]> perLocale = null;
              if (ref == null || (perLocale = ref.get()) == null ||
                  (names = perLocale.get(locale)) == null) {
                  // BEGIN Android-changed: use ICU TimeZoneNames instead of TimeZoneNameUtility.
                  /*
                  names = TimeZoneNameUtility.retrieveDisplayNames(id, locale);
                  if (names == null) {
                      return null;
                  }
                  names = Arrays.copyOfRange(names, 0, 7);
                  names[5] =
                      TimeZoneNameUtility.retrieveGenericDisplayName(id, TimeZone.LONG, locale);
                  if (names[5] == null) {
                      names[5] = names[0]; // use the id
                  }
                  names[6] =
                      TimeZoneNameUtility.retrieveGenericDisplayName(id, TimeZone.SHORT, locale);
                  */
                  TimeZoneNames timeZoneNames = TimeZoneNames.getInstance(locale);
                  names = new String[TYPES.length + 1];
                  // Zeroth index used for id, other indexes based on NameType constant + 1.
                  names[0] = id;
                  String canonicalId = ZoneMeta.getCanonicalCLDRID(id);
                  timeZoneNames.getDisplayNames(canonicalId, TYPES, System.currentTimeMillis(),
                          /* dest */ names, /* destoffset */ 1);
                  if (names == null) {
                      return null;
                  }
                  if (names[1] == null || names[2] == null || names[3] == null || names[4] == null) {
                      // Use "GMT+XX:XX" analogous to java.util.TimeZone.getDisplayName()
                      TimeZone tz = TimeZone.getTimeZone(id);
                      String stdString = TimeZone.createGmtOffsetString(
                              /* includeGmt */ true, /* includeMinuteSeparator */ true,
                              tz.getRawOffset());
                      String dstString = TimeZone.createGmtOffsetString(
                              /* includeGmt */ true, /* includeMinuteSeparator */ true,
                              tz.getRawOffset() + tz.getDSTSavings());
                      names[1] = names[1] != null ? names[1] : stdString;
                      names[2] = names[2] != null ? names[2] : stdString;
                      names[3] = names[3] != null ? names[3] : dstString;
                      names[4] = names[4] != null ? names[4] : dstString;
                  }
                  if (names[5] == null) {
                      names[5] = names[0]; // use the id
                  }
                  // END Android-changed: use ICU TimeZoneNames instead of TimeZoneNameUtility.
                  if (names[6] == null) {
                      names[6] = names[0];
                  }
                  if (perLocale == null) {
                      perLocale = new ConcurrentHashMap<>();
                  }
                  perLocale.put(locale, names);
                  cache.put(id, new SoftReference<>(perLocale));
              }
              switch (type) {
              case STD:
                  return names[textStyle.zoneNameStyleIndex() + 1];
              case DST:
                  return names[textStyle.zoneNameStyleIndex() + 3];
              }
              return names[textStyle.zoneNameStyleIndex() + 5];
          }
  
          @Override
          public boolean format(DateTimePrintContext context, StringBuilder buf) {
              ZoneId zone = context.getValue(TemporalQueries.zoneId());
              if (zone == null) {
                  return false;
              }
              String zname = zone.getId();
              if (!(zone instanceof ZoneOffset)) {
                  TemporalAccessor dt = context.getTemporal();
                  String name = getDisplayName(zname,
                                               dt.isSupported(ChronoField.INSTANT_SECONDS)
                                               ? (zone.getRules().isDaylightSavings(Instant.from(dt)) ? DST : STD)
                                               : GENERIC,
                                               context.getLocale());
                  if (name != null) {
                      zname = name;
                  }
              }
              buf.append(zname);
              return true;
          }
  
          // cache per instance for now
          private final Map<Locale, Entry<Integer, SoftReference<PrefixTree>>>
              cachedTree = new HashMap<>();
          private final Map<Locale, Entry<Integer, SoftReference<PrefixTree>>>
              cachedTreeCI = new HashMap<>();
  
          @Override
          protected PrefixTree getTree(DateTimeParseContext context) {
              if (textStyle == TextStyle.NARROW) {
                  return super.getTree(context);
              }
              Locale locale = context.getLocale();
              boolean isCaseSensitive = context.isCaseSensitive();
              Set<String> regionIds = ZoneRulesProvider.getAvailableZoneIds();
              int regionIdsSize = regionIds.size();
  
              Map<Locale, Entry<Integer, SoftReference<PrefixTree>>> cached =
                  isCaseSensitive ? cachedTree : cachedTreeCI;
  
              Entry<Integer, SoftReference<PrefixTree>> entry = null;
              PrefixTree tree = null;
              String[][] zoneStrings = null;
              if ((entry = cached.get(locale)) == null ||
                  (entry.getKey() != regionIdsSize ||
                  (tree = entry.getValue().get()) == null)) {
                  tree = PrefixTree.newTree(context);
                  // BEGIN Android-changed: use ICU TimeZoneNames to get Zone names.
                  /*
                  zoneStrings = TimeZoneNameUtility.getZoneStrings(locale);
                  for (String[] names : zoneStrings) {
                      String zid = names[0];
                      if (!regionIds.contains(zid)) {
                          continue;
                      }
                      tree.add(zid, zid);    // don't convert zid -> metazone
                      zid = ZoneName.toZid(zid, locale);
                      int i = textStyle == TextStyle.FULL ? 1 : 2;
                      for (; i < names.length; i += 2) {
                          tree.add(names[i], zid);
                      }
                  }
                  // if we have a set of preferred zones, need a copy and
                  // add the preferred zones again to overwrite
                  if (preferredZones != null) {
                      for (String[] names : zoneStrings) {
                          String zid = names[0];
                          if (!preferredZones.contains(zid) || !regionIds.contains(zid)) {
                              continue;
                          }
                          int i = textStyle == TextStyle.FULL ? 1 : 2;
                          for (; i < names.length; i += 2) {
                              tree.add(names[i], zid);
                         }
                      }
                  }
                  */
                  TimeZoneNames timeZoneNames = TimeZoneNames.getInstance(locale);
                  long now = System.currentTimeMillis();
                  TimeZoneNames.NameType[] types =
                          textStyle == TextStyle.FULL ? FULL_TYPES : SHORT_TYPES;
                  String[] names = new String[types.length];
                  for (String zid : regionIds) {
                      tree.add(zid, zid);    // don't convert zid -> metazone
                      zid = ZoneName.toZid(zid, locale);
                      timeZoneNames.getDisplayNames(zid, types, now, names, 0);
                      for (int i = 0; i < names.length; i++) {
                          if (names[i] != null) {
                              tree.add(names[i], zid);
                          }
                      }
                  }
                  // if we have a set of preferred zones, need a copy and
                  // add the preferred zones again to overwrite
                  if (preferredZones != null) {
                      for (String zid : regionIds) {
                          if (!preferredZones.contains(zid)) {
                              continue;
                          }
                          String canonicalId = ZoneName.toZid(zid, locale);
                          timeZoneNames.getDisplayNames(canonicalId, types, now, names, 0);
                          for (int i = 0; i < names.length; i++) {
                              if (names[i] != null) {
                                  tree.add(names[i], zid);
                              }
                          }
                      }
                  }
                  // END Android-changed: use ICU TimeZoneNames to get Zone names.
                  cached.put(locale, new SimpleImmutableEntry<>(regionIdsSize, new SoftReference<>(tree)));
              }
              return tree;
          }
      }
  
      //-----------------------------------------------------------------------
      /**
       * Prints or parses a zone ID.
       */
      static class ZoneIdPrinterParser implements DateTimePrinterParser {
          private final TemporalQuery<ZoneId> query;
          private final String description;
  
          ZoneIdPrinterParser(TemporalQuery<ZoneId> query, String description) {
              this.query = query;
              this.description = description;
          }
  
          @Override
          public boolean format(DateTimePrintContext context, StringBuilder buf) {
              ZoneId zone = context.getValue(query);
              if (zone == null) {
                  return false;
              }
              buf.append(zone.getId());
              return true;
          }
  
          /**
           * The cached tree to speed up parsing.
           */
          private static volatile Entry<Integer, PrefixTree> cachedPrefixTree;
          private static volatile Entry<Integer, PrefixTree> cachedPrefixTreeCI;
  
          protected PrefixTree getTree(DateTimeParseContext context) {
              // prepare parse tree
              Set<String> regionIds = ZoneRulesProvider.getAvailableZoneIds();
              final int regionIdsSize = regionIds.size();
              Entry<Integer, PrefixTree> cached = context.isCaseSensitive()
                                                  ? cachedPrefixTree : cachedPrefixTreeCI;
              if (cached == null || cached.getKey() != regionIdsSize) {
                  synchronized (this) {
                      cached = context.isCaseSensitive() ? cachedPrefixTree : cachedPrefixTreeCI;
                      if (cached == null || cached.getKey() != regionIdsSize) {
                          cached = new SimpleImmutableEntry<>(regionIdsSize, PrefixTree.newTree(regionIds, context));
                          if (context.isCaseSensitive()) {
                              cachedPrefixTree = cached;
                          } else {
                              cachedPrefixTreeCI = cached;
                          }
                      }
                  }
              }
              return cached.getValue();
          }
  
          /**
           * This implementation looks for the longest matching string.
           * For example, parsing Etc/GMT-2 will return Etc/GMC-2 rather than just
           * Etc/GMC although both are valid.
           */
          @Override
          public int parse(DateTimeParseContext context, CharSequence text, int position) {
              int length = text.length();
              if (position > length) {
                  throw new IndexOutOfBoundsException();
              }
              if (position == length) {
                  return ~position;
              }
  
              // handle fixed time-zone IDs
              char nextChar = text.charAt(position);
              if (nextChar == '+' || nextChar == '-') {
                  return parseOffsetBased(context, text, position, position, OffsetIdPrinterParser.INSTANCE_ID_Z);
              } else if (length >= position + 2) {
                  char nextNextChar = text.charAt(position + 1);
                  if (context.charEquals(nextChar, 'U') && context.charEquals(nextNextChar, 'T')) {
                      if (length >= position + 3 && context.charEquals(text.charAt(position + 2), 'C')) {
                          return parseOffsetBased(context, text, position, position + 3, OffsetIdPrinterParser.INSTANCE_ID_ZERO);
                      }
                      return parseOffsetBased(context, text, position, position + 2, OffsetIdPrinterParser.INSTANCE_ID_ZERO);
                  } else if (context.charEquals(nextChar, 'G') && length >= position + 3 &&
                          context.charEquals(nextNextChar, 'M') && context.charEquals(text.charAt(position + 2), 'T')) {
                      return parseOffsetBased(context, text, position, position + 3, OffsetIdPrinterParser.INSTANCE_ID_ZERO);
                  }
              }
  
              // parse
              PrefixTree tree = getTree(context);
              ParsePosition ppos = new ParsePosition(position);
              String parsedZoneId = tree.match(text, ppos);
              if (parsedZoneId == null) {
                  if (context.charEquals(nextChar, 'Z')) {
                      context.setParsed(ZoneOffset.UTC);
                      return position + 1;
                  }
                  return ~position;
              }
              context.setParsed(ZoneId.of(parsedZoneId));
              return ppos.getIndex();
          }
  
          /**
           * Parse an offset following a prefix and set the ZoneId if it is valid.
           * To matching the parsing of ZoneId.of the values are not normalized
           * to ZoneOffsets.
           *
           * @param context the parse context
           * @param text the input text
           * @param prefixPos start of the prefix
           * @param position start of text after the prefix
           * @param parser parser for the value after the prefix
           * @return the position after the parse
           */
          private int parseOffsetBased(DateTimeParseContext context, CharSequence text, int prefixPos, int position, OffsetIdPrinterParser parser) {
              String prefix = text.toString().substring(prefixPos, position).toUpperCase();
              if (position >= text.length()) {
                  context.setParsed(ZoneId.of(prefix));
                  return position;
              }
  
              // Android-added: "GMT0" is considered a valid ZoneId.
              if (text.charAt(position) == '0' && prefix.equals("GMT")) {
                  context.setParsed(ZoneId.of("GMT0"));
                  return position + 1;
              }
  
              // '0' or 'Z' after prefix is not part of a valid ZoneId; use bare prefix
              if (text.charAt(position) == '0' ||
                  context.charEquals(text.charAt(position), 'Z')) {
                  context.setParsed(ZoneId.of(prefix));
                  return position;
              }
  
              DateTimeParseContext newContext = context.copy();
              int endPos = parser.parse(newContext, text, position);
              try {
                  if (endPos < 0) {
                      if (parser == OffsetIdPrinterParser.INSTANCE_ID_Z) {
                          return ~prefixPos;
                      }
                      context.setParsed(ZoneId.of(prefix));
                      return position;
                  }
                  int offset = (int) newContext.getParsed(OFFSET_SECONDS).longValue();
                  ZoneOffset zoneOffset = ZoneOffset.ofTotalSeconds(offset);
                  context.setParsed(ZoneId.ofOffset(prefix, zoneOffset));
                  return endPos;
              } catch (DateTimeException dte) {
                  return ~prefixPos;
              }
          }
  
          @Override
          public String toString() {
              return description;
          }
      }
  
      //-----------------------------------------------------------------------
      /**
       * A String based prefix tree for parsing time-zone names.
       */
      static class PrefixTree {
          protected String key;
          protected String value;
          protected char c0;    // performance optimization to avoid the
                                // boundary check cost of key.charat(0)
          protected PrefixTree child;
          protected PrefixTree sibling;
  
          private PrefixTree(String k, String v, PrefixTree child) {
              this.key = k;
              this.value = v;
              this.child = child;
              if (k.length() == 0){
                  c0 = 0xffff;
              } else {
                  c0 = key.charAt(0);
              }
          }
  
          /**
           * Creates a new prefix parsing tree based on parse context.
           *
           * @param context  the parse context
           * @return the tree, not null
           */
          public static PrefixTree newTree(DateTimeParseContext context) {
              //if (!context.isStrict()) {
              //    return new LENIENT("", null, null);
              //}
              if (context.isCaseSensitive()) {
                  return new PrefixTree("", null, null);
              }
              return new CI("", null, null);
          }
  
          /**
           * Creates a new prefix parsing tree.
           *
           * @param keys  a set of strings to build the prefix parsing tree, not null
           * @param context  the parse context
           * @return the tree, not null
           */
          public static  PrefixTree newTree(Set<String> keys, DateTimeParseContext context) {
              PrefixTree tree = newTree(context);
              for (String k : keys) {
                  tree.add0(k, k);
              }
              return tree;
          }
  
          /**
           * Clone a copy of this tree
           */
          public PrefixTree copyTree() {
              PrefixTree copy = new PrefixTree(key, value, null);
              if (child != null) {
                  copy.child = child.copyTree();
              }
              if (sibling != null) {
                  copy.sibling = sibling.copyTree();
              }
              return copy;
          }
  
  
          /**
           * Adds a pair of {key, value} into the prefix tree.
           *
           * @param k  the key, not null
           * @param v  the value, not null
           * @return  true if the pair is added successfully
           */
          public boolean add(String k, String v) {
              return add0(k, v);
          }
  
          private boolean add0(String k, String v) {
              k = toKey(k);
              int prefixLen = prefixLength(k);
              if (prefixLen == key.length()) {
                  if (prefixLen < k.length()) {  // down the tree
                      String subKey = k.substring(prefixLen);
                      PrefixTree c = child;
                      while (c != null) {
                          if (isEqual(c.c0, subKey.charAt(0))) {
                              return c.add0(subKey, v);
                          }
                          c = c.sibling;
                      }
                      // add the node as the child of the current node
                      c = newNode(subKey, v, null);
                      c.sibling = child;
                      child = c;
                      return true;
                  }
                  // have an existing <key, value> already, overwrite it
                  // if (value != null) {
                  //    return false;
                  //}
                  value = v;
                  return true;
              }
              // split the existing node
              PrefixTree n1 = newNode(key.substring(prefixLen), value, child);
              key = k.substring(0, prefixLen);
              child = n1;
              if (prefixLen < k.length()) {
                  PrefixTree n2 = newNode(k.substring(prefixLen), v, null);
                  child.sibling = n2;
                  value = null;
              } else {
                  value = v;
              }
              return true;
          }
  
          /**
           * Match text with the prefix tree.
           *
           * @param text  the input text to parse, not null
           * @param off  the offset position to start parsing at
           * @param end  the end position to stop parsing
           * @return the resulting string, or null if no match found.
           */
          public String match(CharSequence text, int off, int end) {
              if (!prefixOf(text, off, end)){
                  return null;
              }
              if (child != null && (off += key.length()) != end) {
                  PrefixTree c = child;
                  do {
                      if (isEqual(c.c0, text.charAt(off))) {
                          String found = c.match(text, off, end);
                          if (found != null) {
                              return found;
                          }
                          return value;
                      }
                      c = c.sibling;
                  } while (c != null);
              }
              return value;
          }
  
          /**
           * Match text with the prefix tree.
           *
           * @param text  the input text to parse, not null
           * @param pos  the position to start parsing at, from 0 to the text
           *  length. Upon return, position will be updated to the new parse
           *  position, or unchanged, if no match found.
           * @return the resulting string, or null if no match found.
           */
          public String match(CharSequence text, ParsePosition pos) {
              int off = pos.getIndex();
              int end = text.length();
              if (!prefixOf(text, off, end)){
                  return null;
              }
              off += key.length();
              if (child != null && off != end) {
                  PrefixTree c = child;
                  do {
                      if (isEqual(c.c0, text.charAt(off))) {
                          pos.setIndex(off);
                          String found = c.match(text, pos);
                          if (found != null) {
                              return found;
                          }
                          break;
                      }
                      c = c.sibling;
                  } while (c != null);
              }
              pos.setIndex(off);
              return value;
          }
  
          protected String toKey(String k) {
              return k;
          }
  
          protected PrefixTree newNode(String k, String v, PrefixTree child) {
              return new PrefixTree(k, v, child);
          }
  
          protected boolean isEqual(char c1, char c2) {
              return c1 == c2;
          }
  
          protected boolean prefixOf(CharSequence text, int off, int end) {
              if (text instanceof String) {
                  return ((String)text).startsWith(key, off);
              }
              int len = key.length();
              if (len > end - off) {
                  return false;
              }
              int off0 = 0;
              while (len-- > 0) {
                  if (!isEqual(key.charAt(off0++), text.charAt(off++))) {
                      return false;
                  }
              }
              return true;
          }
  
          private int prefixLength(String k) {
              int off = 0;
              while (off < k.length() && off < key.length()) {
                  if (!isEqual(k.charAt(off), key.charAt(off))) {
                      return off;
                  }
                  off++;
              }
              return off;
          }
  
          /**
           * Case Insensitive prefix tree.
           */
          private static class CI extends PrefixTree {
  
              private CI(String k, String v, PrefixTree child) {
                  super(k, v, child);
              }
  
              @Override
              protected CI newNode(String k, String v, PrefixTree child) {
                  return new CI(k, v, child);
              }
  
              @Override
              protected boolean isEqual(char c1, char c2) {
                  return DateTimeParseContext.charEqualsIgnoreCase(c1, c2);
              }
  
              @Override
              protected boolean prefixOf(CharSequence text, int off, int end) {
                  int len = key.length();
                  if (len > end - off) {
                      return false;
                  }
                  int off0 = 0;
                  while (len-- > 0) {
                      if (!isEqual(key.charAt(off0++), text.charAt(off++))) {
                          return false;
                      }
                  }
                  return true;
              }
          }
  
          /**
           * Lenient prefix tree. Case insensitive and ignores characters
           * like space, underscore and slash.
           */
          private static class LENIENT extends CI {
  
              private LENIENT(String k, String v, PrefixTree child) {
                  super(k, v, child);
              }
  
              @Override
              protected CI newNode(String k, String v, PrefixTree child) {
                  return new LENIENT(k, v, child);
              }
  
              private boolean isLenientChar(char c) {
                  return c == ' ' || c == '_' || c == '/';
              }
  
              protected String toKey(String k) {
                  for (int i = 0; i < k.length(); i++) {
                      if (isLenientChar(k.charAt(i))) {
                          StringBuilder sb = new StringBuilder(k.length());
                          sb.append(k, 0, i);
                          i++;
                          while (i < k.length()) {
                              if (!isLenientChar(k.charAt(i))) {
                                  sb.append(k.charAt(i));
                              }
                              i++;
                          }
                          return sb.toString();
                      }
                  }
                  return k;
              }
  
              @Override
              public String match(CharSequence text, ParsePosition pos) {
                  int off = pos.getIndex();
                  int end = text.length();
                  int len = key.length();
                  int koff = 0;
                  while (koff < len && off < end) {
                      if (isLenientChar(text.charAt(off))) {
                          off++;
                          continue;
                      }
                      if (!isEqual(key.charAt(koff++), text.charAt(off++))) {
                          return null;
                      }
                  }
                  if (koff != len) {
                      return null;
                  }
                  if (child != null && off != end) {
                      int off0 = off;
                      while (off0 < end && isLenientChar(text.charAt(off0))) {
                          off0++;
                      }
                      if (off0 < end) {
                          PrefixTree c = child;
                          do {
                              if (isEqual(c.c0, text.charAt(off0))) {
                                  pos.setIndex(off0);
                                  String found = c.match(text, pos);
                                  if (found != null) {
                                      return found;
                                  }
                                  break;
                              }
                              c = c.sibling;
                          } while (c != null);
                      }
                  }
                  pos.setIndex(off);
                  return value;
              }
          }
      }
  
      //-----------------------------------------------------------------------
      /**
       * Prints or parses a chronology.
       */
      static final class ChronoPrinterParser implements DateTimePrinterParser {
          /** The text style to output, null means the ID. */
          private final TextStyle textStyle;
  
          ChronoPrinterParser(TextStyle textStyle) {
              // validated by caller
              this.textStyle = textStyle;
          }
  
          @Override
          public boolean format(DateTimePrintContext context, StringBuilder buf) {
              Chronology chrono = context.getValue(TemporalQueries.chronology());
              if (chrono == null) {
                  return false;
              }
              if (textStyle == null) {
                  buf.append(chrono.getId());
              } else {
                  buf.append(getChronologyName(chrono, context.getLocale()));
              }
              return true;
          }
  
          @Override
          public int parse(DateTimeParseContext context, CharSequence text, int position) {
              // simple looping parser to find the chronology
              if (position < 0 || position > text.length()) {
                  throw new IndexOutOfBoundsException();
              }
              Set<Chronology> chronos = Chronology.getAvailableChronologies();
              Chronology bestMatch = null;
              int matchLen = -1;
              for (Chronology chrono : chronos) {
                  String name;
                  if (textStyle == null) {
                      name = chrono.getId();
                  } else {
                      name = getChronologyName(chrono, context.getLocale());
                  }
                  int nameLen = name.length();
                  if (nameLen > matchLen && context.subSequenceEquals(text, position, name, 0, nameLen)) {
                      bestMatch = chrono;
                      matchLen = nameLen;
                  }
              }
              if (bestMatch == null) {
                  return ~position;
              }
              context.setParsed(bestMatch);
              return position + matchLen;
          }
  
          /**
           * Returns the chronology name of the given chrono in the given locale
           * if available, or the chronology Id otherwise. The regular ResourceBundle
           * search path is used for looking up the chronology name.
           *
           * @param chrono  the chronology, not null
           * @param locale  the locale, not null
           * @return the chronology name of chrono in locale, or the id if no name is available
           * @throws NullPointerException if chrono or locale is null
           */
          private String getChronologyName(Chronology chrono, Locale locale) {
              // Android-changed: Use ICU LocaleDisplayNames. http://b/28832222
              // String key = "calendarname." + chrono.getCalendarType();
              // String name = DateTimeTextProvider.getLocalizedResource(key, locale);
              LocaleDisplayNames displayNames = LocaleDisplayNames.getInstance(ULocale.forLocale(locale));
              String name = displayNames.keyValueDisplayName("calendar", chrono.getCalendarType());
              return name != null ? name : chrono.getId();
          }
      }
  
      //-----------------------------------------------------------------------
      /**
       * Prints or parses a localized pattern.
       */
      static final class LocalizedPrinterParser implements DateTimePrinterParser {
          /** Cache of formatters. */
          private static final ConcurrentMap<String, DateTimeFormatter> FORMATTER_CACHE = new ConcurrentHashMap<>(16, 0.75f, 2);
  
          private final FormatStyle dateStyle;
          private final FormatStyle timeStyle;
  
          /**
           * Constructor.
           *
           * @param dateStyle  the date style to use, may be null
           * @param timeStyle  the time style to use, may be null
           */
          LocalizedPrinterParser(FormatStyle dateStyle, FormatStyle timeStyle) {
              // validated by caller
              this.dateStyle = dateStyle;
              this.timeStyle = timeStyle;
          }
  
          @Override
          public boolean format(DateTimePrintContext context, StringBuilder buf) {
              Chronology chrono = Chronology.from(context.getTemporal());
              return formatter(context.getLocale(), chrono).toPrinterParser(false).format(context, buf);
          }
  
          @Override
          public int parse(DateTimeParseContext context, CharSequence text, int position) {
              Chronology chrono = context.getEffectiveChronology();
              return formatter(context.getLocale(), chrono).toPrinterParser(false).parse(context, text, position);
          }
  
          /**
           * Gets the formatter to use.
           * <p>
           * The formatter will be the most appropriate to use for the date and time style in the locale.
           * For example, some locales will use the month name while others will use the number.
           *
           * @param locale  the locale to use, not null
           * @param chrono  the chronology to use, not null
           * @return the formatter, not null
           * @throws IllegalArgumentException if the formatter cannot be found
           */
          private DateTimeFormatter formatter(Locale locale, Chronology chrono) {
              String key = chrono.getId() + '|' + locale.toString() + '|' + dateStyle + timeStyle;
              DateTimeFormatter formatter = FORMATTER_CACHE.get(key);
              if (formatter == null) {
                  String pattern = getLocalizedDateTimePattern(dateStyle, timeStyle, chrono, locale);
                  formatter = new DateTimeFormatterBuilder().appendPattern(pattern).toFormatter(locale);
                  DateTimeFormatter old = FORMATTER_CACHE.putIfAbsent(key, formatter);
                  if (old != null) {
                      formatter = old;
                  }
              }
              return formatter;
          }
  
          @Override
          public String toString() {
              return "Localized(" + (dateStyle != null ? dateStyle : "") + "," +
                  (timeStyle != null ? timeStyle : "") + ")";
          }
      }
  
      //-----------------------------------------------------------------------
      /**
       * Prints or parses a localized pattern from a localized field.
       * The specific formatter and parameters is not selected until the
       * the field is to be printed or parsed.
       * The locale is needed to select the proper WeekFields from which
       * the field for day-of-week, week-of-month, or week-of-year is selected.
       */
      static final class WeekBasedFieldPrinterParser implements DateTimePrinterParser {
          private char chr;
          private int count;
  
          /**
           * Constructor.
           *
           * @param chr the pattern format letter that added this PrinterParser.
           * @param count the repeat count of the format letter
           */
          WeekBasedFieldPrinterParser(char chr, int count) {
              this.chr = chr;
              this.count = count;
          }
  
          @Override
          public boolean format(DateTimePrintContext context, StringBuilder buf) {
              return printerParser(context.getLocale()).format(context, buf);
          }
  
          @Override
          public int parse(DateTimeParseContext context, CharSequence text, int position) {
              return printerParser(context.getLocale()).parse(context, text, position);
          }
  
          /**
           * Gets the printerParser to use based on the field and the locale.
           *
           * @param locale  the locale to use, not null
           * @return the formatter, not null
           * @throws IllegalArgumentException if the formatter cannot be found
           */
          private DateTimePrinterParser printerParser(Locale locale) {
              WeekFields weekDef = WeekFields.of(locale);
              TemporalField field = null;
              switch (chr) {
                  case 'Y':
                      field = weekDef.weekBasedYear();
                      if (count == 2) {
                          return new ReducedPrinterParser(field, 2, 2, 0, ReducedPrinterParser.BASE_DATE, 0);
                      } else {
                          return new NumberPrinterParser(field, count, 19,
                                  (count < 4) ? SignStyle.NORMAL : SignStyle.EXCEEDS_PAD, -1);
                      }
                  case 'e':
                  case 'c':
                      field = weekDef.dayOfWeek();
                      break;
                  case 'w':
                      field = weekDef.weekOfWeekBasedYear();
                      break;
                  case 'W':
                      field = weekDef.weekOfMonth();
                      break;
                  default:
                      throw new IllegalStateException("unreachable");
              }
              return new NumberPrinterParser(field, (count == 2 ? 2 : 1), 2, SignStyle.NOT_NEGATIVE);
          }
  
          @Override
          public String toString() {
              StringBuilder sb = new StringBuilder(30);
              sb.append("Localized(");
              if (chr == 'Y') {
                  if (count == 1) {
                      sb.append("WeekBasedYear");
                  } else if (count == 2) {
                      sb.append("ReducedValue(WeekBasedYear,2,2,2000-01-01)");
                  } else {
                      sb.append("WeekBasedYear,").append(count).append(",")
                              .append(19).append(",")
                              .append((count < 4) ? SignStyle.NORMAL : SignStyle.EXCEEDS_PAD);
                  }
              } else {
                  switch (chr) {
                      case 'c':
                      case 'e':
                          sb.append("DayOfWeek");
                          break;
                      case 'w':
                          sb.append("WeekOfWeekBasedYear");
                          break;
                      case 'W':
                          sb.append("WeekOfMonth");
                          break;
                      default:
                          break;
                  }
                  sb.append(",");
                  sb.append(count);
              }
              sb.append(")");
              return sb.toString();
          }
      }
  
      //-------------------------------------------------------------------------
      /**
       * Length comparator.
       */
      static final Comparator<String> LENGTH_SORT = new Comparator<String>() {
          @Override
          public int compare(String str1, String str2) {
              return str1.length() == str2.length() ? str1.compareTo(str2) : str1.length() - str2.length();
          }
      };
  }
  