content: /*
   * Licensed to the Apache Software Foundation (ASF) under one or more
   * contributor license agreements.  See the NOTICE file distributed with
   * this work for additional information regarding copyright ownership.
   * The ASF licenses this file to you under the Apache License, Version 2.0
   * (the "License"); you may not use this file except in compliance with
   * the License.  You may obtain a copy of the License at
   *
   * http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  package org.apache.calcite.util.format.postgresql.format.compiled;
  
  import org.apache.calcite.util.format.postgresql.ChronoUnitEnum;
  import org.apache.calcite.util.format.postgresql.PatternModifier;
  
  import java.text.ParseException;
  import java.text.ParsePosition;
  import java.util.Locale;
  import java.util.Set;
  
  /**
   * A single date/time format compiled component such as "YYYY" or "MI". A compiled component
   * is a format component along with any flags it had. Adds the ability to parse a string.
   */
  public abstract class CompiledPattern implements CompiledItem {
    private final ChronoUnitEnum chronoUnit;
    protected final Set<PatternModifier> modifiers;
  
    protected CompiledPattern(ChronoUnitEnum chronoUnit, Set<PatternModifier> modifiers) {
      this.chronoUnit = chronoUnit;
      this.modifiers = modifiers;
    }
  
    /**
     * Get the ChronoUnitEnum value that this pattern is for.
     *
     * @return a ChronoUnitEnum value
     */
    public ChronoUnitEnum getChronoUnit() {
      return chronoUnit;
    }
  
    /**
     * Parse this date/time component from a String.
     *
     * @param inputPosition starting position for parsing
     * @param input full string that will be parsed
     * @param enforceLength whether to limit the length of characters read. Needed when one
     *                      sequence of digits is followed by another (such as YYYYDD).
     * @param locale Locale to use for parsing day and month names if the TM flag was present
     * @return the integer value of the parsed date/time component
     * @throws ParseException if unable to parse a value from input
     */
    public abstract int parseValue(ParsePosition inputPosition, String input, boolean enforceLength,
        Locale locale) throws ParseException;
  
    @Override public int getFormatPatternLength() {
      return 2 * modifiers.size() + getBaseFormatPatternLength();
    }
  
    /**
     * Returns the length of the format pattern without modifiers.
     *
     * @return length of the format pattern
     */
    protected abstract int getBaseFormatPatternLength();
  
    /**
     * Does this pattern match a sequence of digits.
     *
     * @return true if this pattern matches a sequence of digits
     */
    public boolean isNumeric() {
      return false;
    }
  }
  