content: /*
   * Copyright (c) 1997, 2013, 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
   * or visit www.oracle.com if you need additional information or have any
   * questions.
   */
  
  package java.text;
  
  import java.io.InvalidObjectException;
  import java.io.Serializable;
  import java.util.HashMap;
  import java.util.Map;
  import java.util.Set;
  
  /**
   * An {@code AttributedCharacterIterator} allows iteration through both text and
   * related attribute information.
   *
   * <p>
   * An attribute is a key/value pair, identified by the key.  No two
   * attributes on a given character can have the same key.
   *
   * <p>The values for an attribute are immutable, or must not be mutated
   * by clients or storage.  They are always passed by reference, and not
   * cloned.
   *
   * <p>A <em>run with respect to an attribute</em> is a maximum text range for
   * which:
   * <ul>
   * <li>the attribute is undefined or {@code null} for the entire range, or
   * <li>the attribute value is defined and has the same non-{@code null} value for the
   *     entire range.
   * </ul>
   *
   * <p>A <em>run with respect to a set of attributes</em> is a maximum text range for
   * which this condition is met for each member attribute.
   *
   * <p>When getting a run with no explicit attributes specified (i.e.,
   * calling {@link #getRunStart()} and {@link #getRunLimit()}), any
   * contiguous text segments having the same attributes (the same set
   * of attribute/value pairs) are treated as separate runs if the
   * attributes have been given to those text segments separately.
   *
   * <p>The returned indexes are limited to the range of the iterator.
   *
   * <p>The returned attribute information is limited to runs that contain
   * the current character.
   *
   * <p>
   * Attribute keys are instances of {@link Attribute} and its
   * subclasses, such as {@link java.awt.font.TextAttribute}.
   *
   * @see Attribute
   * @see java.awt.font.TextAttribute
   * @see AttributedString
   * @see Annotation
   * @since 1.2
   */
  
  public interface AttributedCharacterIterator extends CharacterIterator {
  
      /**
       * Defines attribute keys that are used to identify text attributes. These
       * keys are used in {@code AttributedCharacterIterator} and {@code AttributedString}.
       * @see AttributedCharacterIterator
       * @see AttributedString
       * @since 1.2
       */
  
      public static class Attribute implements Serializable {
  
          /**
           * The name of this {@code Attribute}. The name is used primarily by {@code readResolve}
           * to look up the corresponding predefined instance when deserializing
           * an instance.
           * @serial
           */
          private String name;
  
          // table of all instances in this class, used by readResolve
          private static final Map<String, Attribute> instanceMap = new HashMap<>(7);
  
          /**
           * Constructs an {@code Attribute} with the given name.
           *
           * @param name the name of {@code Attribute}
           */
          protected Attribute(String name) {
              this.name = name;
              if (this.getClass() == Attribute.class) {
                  instanceMap.put(name, this);
              }
          }
  
          /**
           * Compares two objects for equality. This version only returns true
           * for {@code x.equals(y)} if {@code x} and {@code y} refer
           * to the same object, and guarantees this for all subclasses.
           */
          public final boolean equals(Object obj) {
              return super.equals(obj);
          }
  
          /**
           * Returns a hash code value for the object. This version is identical to
           * the one in {@code Object}, but is also final.
           */
          public final int hashCode() {
              return super.hashCode();
          }
  
          /**
           * Returns a string representation of the object. This version returns the
           * concatenation of class name, {@code "("}, a name identifying the attribute
           * and {@code ")"}.
           */
          public String toString() {
              return getClass().getName() + "(" + name + ")";
          }
  
          /**
           * Returns the name of the attribute.
           *
           * @return the name of {@code Attribute}
           */
          protected String getName() {
              return name;
          }
  
          /**
           * Resolves instances being deserialized to the predefined constants.
           *
           * @return the resolved {@code Attribute} object
           * @throws InvalidObjectException if the object to resolve is not
           *                                an instance of {@code Attribute}
           */
          protected Object readResolve() throws InvalidObjectException {
              if (this.getClass() != Attribute.class) {
                  throw new InvalidObjectException("subclass didn't correctly implement readResolve");
              }
  
              Attribute instance = instanceMap.get(getName());
              if (instance != null) {
                  return instance;
              } else {
                  throw new InvalidObjectException("unknown attribute name");
              }
          }
  
          /**
           * Attribute key for the language of some text.
           * <p> Values are instances of {@link java.util.Locale Locale}.
           * @see java.util.Locale
           */
          public static final Attribute LANGUAGE = new Attribute("language");
  
          /**
           * Attribute key for the reading of some text. In languages where the written form
           * and the pronunciation of a word are only loosely related (such as Japanese),
           * it is often necessary to store the reading (pronunciation) along with the
           * written form.
           * <p>Values are instances of {@link Annotation} holding instances of {@link String}.
           *
           * @see Annotation
           * @see String
           */
          public static final Attribute READING = new Attribute("reading");
  
          /**
           * Attribute key for input method segments. Input methods often break
           * up text into segments, which usually correspond to words.
           * <p>Values are instances of {@link Annotation} holding a {@code null} reference.
           * @see Annotation
           */
          public static final Attribute INPUT_METHOD_SEGMENT = new Attribute("input_method_segment");
  
          // make sure the serial version doesn't change between compiler versions
          private static final long serialVersionUID = -9142742483513960612L;
  
      };
  
      /**
       * Returns the index of the first character of the run
       * with respect to all attributes containing the current character.
       *
       * <p>Any contiguous text segments having the same attributes (the
       * same set of attribute/value pairs) are treated as separate runs
       * if the attributes have been given to those text segments separately.
       *
       * @return the index of the first character of the run
       */
      public int getRunStart();
  
      /**
       * Returns the index of the first character of the run
       * with respect to the given {@code attribute} containing the current character.
       *
       * @param attribute the desired attribute.
       * @return the index of the first character of the run
       */
      public int getRunStart(Attribute attribute);
  
      /**
       * Returns the index of the first character of the run
       * with respect to the given {@code attributes} containing the current character.
       *
       * @param attributes a set of the desired attributes.
       * @return the index of the first character of the run
       */
      public int getRunStart(Set<? extends Attribute> attributes);
  
      /**
       * Returns the index of the first character following the run
       * with respect to all attributes containing the current character.
       *
       * <p>Any contiguous text segments having the same attributes (the
       * same set of attribute/value pairs) are treated as separate runs
       * if the attributes have been given to those text segments separately.
       *
       * @return the index of the first character following the run
       */
      public int getRunLimit();
  
      /**
       * Returns the index of the first character following the run
       * with respect to the given {@code attribute} containing the current character.
       *
       * @param attribute the desired attribute
       * @return the index of the first character following the run
       */
      public int getRunLimit(Attribute attribute);
  
      /**
       * Returns the index of the first character following the run
       * with respect to the given {@code attributes} containing the current character.
       *
       * @param attributes a set of the desired attributes
       * @return the index of the first character following the run
       */
      public int getRunLimit(Set<? extends Attribute> attributes);
  
      /**
       * Returns a map with the attributes defined on the current
       * character.
       *
       * @return a map with the attributes defined on the current character
       */
      public Map<Attribute,Object> getAttributes();
  
      /**
       * Returns the value of the named {@code attribute} for the current character.
       * Returns {@code null} if the {@code attribute} is not defined.
       *
       * @param attribute the desired attribute
       * @return the value of the named {@code attribute} or {@code null}
       */
      public Object getAttribute(Attribute attribute);
  
      /**
       * Returns the keys of all attributes defined on the
       * iterator's text range. The set is empty if no
       * attributes are defined.
       *
       * @return the keys of all attributes
       */
      public Set<Attribute> getAllAttributeKeys();
  };
  