/*
 * Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 */

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 AttributedCharacterIterator.Attribute} and its
 * subclasses, such as {@link java.awt.font.TextAttribute}.
 *
 * @see AttributedCharacterIterator.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 java.lang.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();
};