/*
 * Copyright (c) 1997, 2004, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
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 *
 */

package javax.accessibility;

import java.util.Vector;
import java.util.Locale;
import java.util.MissingResourceException;
import java.util.ResourceBundle;

/**
 * Class AccessibleStateSet determines a component's state set. The state set
 * of a component is a set of AccessibleState objects and descriptions. E.G., The
 * current overall state of the object, such as whether it is enabled,
 * has focus, etc.
 *
 * @see AccessibleState
 *
 * @author Willie Walker
 */
public class AccessibleStateSet {

 /**
 * Each entry in the Vector represents an AccessibleState.
 * @see #add
 * @see #addAll
 * @see #remove
 * @see #contains
 * @see #toArray
 * @see #clear
 */
 protected Vector<AccessibleState> states = null;

 /**
 * Creates a new empty state set.
 */
 public AccessibleStateSet() {
 states = null;
 }

 /**
 * Creates a new state with the initial set of states contained in
 * the array of states passed in. Duplicate entries are ignored.
 *
 * @param states an array of AccessibleState describing the state set.
 */
 public AccessibleStateSet(AccessibleState[] states) {
 if (states.length != 0) {
 this.states = new Vector(states.length);
 for (int i = 0; i < states.length; i++) {
 if (!this.states.contains(states[i])) {
 this.states.addElement(states[i]);
 }
 }
 }
 }

 /**
 * Adds a new state to the current state set if it is not already
 * present. If the state is already in the state set, the state
 * set is unchanged and the return value is false. Otherwise,
 * the state is added to the state set and the return value is
 * true.
 * @param state the state to add to the state set
 * @return true if state is added to the state set; false if the state set
 * is unchanged
 */
 public boolean add(AccessibleState state) {
 // [[[ PENDING: WDW - the implementation of this does not need
 // to always use a vector of states. It could be improved by
 // caching the states as a bit set.]]]
 if (states == null) {
 states = new Vector();
 }

 if (!states.contains(state)) {
 states.addElement(state);
 return true;
 } else {
 return false;
 }
 }

 /**
 * Adds all of the states to the existing state set. Duplicate entries
 * are ignored.
 * @param states AccessibleState array describing the state set.
 */
 public void addAll(AccessibleState[] states) {
 if (states.length != 0) {
 if (this.states == null) {
 this.states = new Vector(states.length);
 }
 for (int i = 0; i < states.length; i++) {
 if (!this.states.contains(states[i])) {
 this.states.addElement(states[i]);
 }
 }
 }
 }

 /**
 * Removes a state from the current state set. If the state is not
 * in the set, the state set will be unchanged and the return value
 * will be false. If the state is in the state set, it will be removed
 * from the set and the return value will be true.
 *
 * @param state the state to remove from the state set
 * @return true if the state is in the state set; false if the state set
 * will be unchanged
 */
 public boolean remove(AccessibleState state) {
 if (states == null) {
 return false;
 } else {
 return states.removeElement(state);
 }
 }

 /**
 * Removes all the states from the current state set.
 */
 public void clear() {
 if (states != null) {
 states.removeAllElements();
 }
 }

 /**
 * Checks if the current state is in the state set.
 * @param state the state
 * @return true if the state is in the state set; otherwise false
 */
 public boolean contains(AccessibleState state) {
 if (states == null) {
 return false;
 } else {
 return states.contains(state);
 }
 }

 /**
 * Returns the current state set as an array of AccessibleState
 * @return AccessibleState array containing the current state.
 */
 public AccessibleState[] toArray() {
 if (states == null) {
 return new AccessibleState[0];
 } else {
 AccessibleState[] stateArray = new AccessibleState[states.size()];
 for (int i = 0; i < stateArray.length; i++) {
 stateArray[i] = (AccessibleState) states.elementAt(i);
 }
 return stateArray;
 }
 }

 /**
 * Creates a localized String representing all the states in the set
 * using the default locale.
 *
 * @return comma separated localized String
 * @see AccessibleBundle#toDisplayString
 */
 public String toString() {
 String ret = null;
 if ((states != null) && (states.size() > 0)) {
 ret = ((AccessibleState) (states.elementAt(0))).toDisplayString();
 for (int i = 1; i < states.size(); i++) {
 ret = ret + ","
 + ((AccessibleState) (states.elementAt(i))).
 toDisplayString();
 }
 }
 return ret;
 }
}