/*
 * @(#)ActionMap.java	1.16 06/04/07
 *
 * Copyright 2006 Sun Microsystems, Inc. All rights reserved.
 * SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 */
package javax.swing;

import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.Serializable;
import java.util.HashMap;
import java.util.Set;

/**
 * <code>ActionMap</code> provides mappings from
 * <code>Object</code>s
 * (called <em>keys</em> or <em><code>Action</code> names</em>)
 * to <code>Action</code>s.
 * An <code>ActionMap</code> is usually used with an <code>InputMap</code>
 * to locate a particular action
 * when a key is pressed. As with <code>InputMap</code>,
 * an <code>ActionMap</code> can have a parent 
 * that is searched for keys not defined in the <code>ActionMap</code>.
 * <p>As with <code>InputMap</code> if you create a cycle, eg:
 * <pre>
 *   ActionMap am = new ActionMap();
 *   ActionMap bm = new ActionMap():
 *   am.setParent(bm);
 *   bm.setParent(am);
 * </pre>
 * some of the methods will cause a StackOverflowError to be thrown.
 *
 * @see InputMap
 *
 * @version 1.16 04/07/06
 * @author Scott Violet
 * @since 1.3
 */
public class ActionMap implements Serializable {
    /** Handles the mapping between Action name and Action. */
    private transient ArrayTable     arrayTable;
    /** Parent that handles any bindings we don't contain. */
    private ActionMap                               parent;


    /**
     * Creates an <code>ActionMap</code> with no parent and no mappings.
     */
    public ActionMap() {
    }

    /**
     * Sets this <code>ActionMap</code>'s parent.
     * 
     * @param map  the <code>ActionMap</code> that is the parent of this one
     */
    public void setParent(ActionMap map) {
	this.parent = map;
    }

    /**
     * Returns this <code>ActionMap</code>'s parent.
     * 
     * @return the <code>ActionMap</code> that is the parent of this one,
     * 	       or null if this <code>ActionMap</code> has no parent
     */
    public ActionMap getParent() {
	return parent;
    }

    /**
     * Adds a binding for <code>key</code> to <code>action</code>.
     * If <code>action</code> is null, this removes the current binding
     * for <code>key</code>.
     * <p>In most instances, <code>key</code> will be
     * <code>action.getValue(NAME)</code>.
     */
    public void put(Object key, Action action) {
	if (key == null) {
	    return;
	}
	if (action == null) {
	    remove(key);
	}
	else {
	    if (arrayTable == null) {
		arrayTable = new ArrayTable();
	    }
	    arrayTable.put(key, action);
	}
    }

    /**
     * Returns the binding for <code>key</code>, messaging the 
     * parent <code>ActionMap</code> if the binding is not locally defined.
     */
    public Action get(Object key) {
	Action value = (arrayTable == null) ? null :