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	/*
	* Copyright (c) 1999, 2011, 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 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>InputMap</code> provides a binding between an input event
	* (currently only <code>KeyStroke</code>s are used)
	* and an <code>Object</code>. <code>InputMap</code>s
	* are usually used with an <code>ActionMap</code>,
	* to determine an <code>Action</code> to perform
	* when a key is pressed.
	* An <code>InputMap</code> can have a parent
	* that is searched for bindings not defined in the <code>InputMap</code>.
	* <p>As with <code>ActionMap</code> if you create a cycle, eg:
	* <pre>
	* InputMap am = new InputMap();
	* InputMap bm = new InputMap():
	* am.setParent(bm);
	* bm.setParent(am);
	* </pre>
	* some of the methods will cause a StackOverflowError to be thrown.
	*
	* @author Scott Violet
	* @since 1.3
	*/
	@SuppressWarnings("serial")
	public class InputMap implements Serializable {
	/** Handles the mapping between KeyStroke and Action name. */
	private transient ArrayTable arrayTable;
	/** Parent that handles any bindings we don't contain. */
	private InputMap parent;


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

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

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

	/**
	* Adds a binding for <code>keyStroke</code> to <code>actionMapKey</code>.
	* If <code>actionMapKey</code> is null, this removes the current binding
	* for <code>keyStroke</code>.
	*/
	public void put(KeyStroke keyStroke, Object actionMapKey) {
	if (keyStroke == null) {
	return;
	}
	if (actionMapKey == null) {
	remove(keyStroke);
	}
	else {
	if (arrayTable == null) {
	arrayTable = new ArrayTable();
	}
	arrayTable.put(keyStroke, actionMapKey);
	}
	}

	/**
	* Returns the binding for <code>keyStroke</code>, messaging the
	* parent <code>InputMap</code> if the binding is not locally defined.
	*/
	public Object get(KeyStroke keyStroke) {
	if (arrayTable == null) {
	InputMap parent = getParent();

	if (parent != null) {
	return parent.get(keyStroke);
	}
	return null;
	}
	Object value = arrayTable.get(keyStroke);

	if (value == null) {
	InputMap parent = getParent();

	if (parent != null) {
	return parent.get(keyStroke);
	}
	}
	return value;
	}

	/**
	* Removes the binding for <code>key</code> from this
	* <code>InputMap</code>.
	*/
	public void remove(KeyStroke key) {
	if (arrayTable != null) {
	arrayTable.remove(key);
	}
	}

	/**
	* Removes all the mappings from this <code>InputMap</code>.
	*/
	public void clear() {
	if (arrayTable != null) {
	arrayTable.clear();
	}
	}

	/**
	* Returns the <code>KeyStroke</code>s that are bound in this <code>InputMap</code>.
	*/
	public KeyStroke[] keys() {
	if (arrayTable == null) {
	return null;
	}
	KeyStroke[] keys = new KeyStroke[arrayTable.size()];
	arrayTable.getKeys(keys);
	return keys;
	}

	/**
	* Returns the number of <code>KeyStroke</code> bindings.
	*/
	public int size() {
	if (arrayTable == null) {
	return 0;
	}
	return arrayTable.size();
	}

	/**
	* Returns an array of the <code>KeyStroke</code>s defined in this
	* <code>InputMap</code> and its parent. This differs from <code>keys()</code> in that
	* this method includes the keys defined in the parent.
	*/
	public KeyStroke[] allKeys() {
	int count = size();
	InputMap parent = getParent();

	if (count == 0) {
	if (parent != null) {
	return parent.allKeys();
	}
	return keys();
	}
	if (parent == null) {
	return keys();
	}
	KeyStroke[] keys = keys();
	KeyStroke[] pKeys = parent.allKeys();

	if (pKeys == null) {
	return keys;
	}
	if (keys == null) {
	// Should only happen if size() != keys.length, which should only
	// happen if mutated from multiple threads (or a bogus subclass).
	return pKeys;
	}

	HashMap<KeyStroke, KeyStroke> keyMap = new HashMap<KeyStroke, KeyStroke>();
	int counter;

	for (counter = keys.length - 1; counter >= 0; counter--) {
	keyMap.put(keys[counter], keys[counter]);
	}
	for (counter = pKeys.length - 1; counter >= 0; counter--) {
	keyMap.put(pKeys[counter], pKeys[counter]);
	}

	KeyStroke[] allKeys = new KeyStroke[keyMap.size()];

	return keyMap.keySet().toArray(allKeys);
	}

	private void writeObject(ObjectOutputStream s) throws IOException {
	s.defaultWriteObject();

	ArrayTable.writeArrayTable(s, arrayTable);
	}

	private void readObject(ObjectInputStream s) throws ClassNotFoundException,
	IOException {
	s.defaultReadObject();
	for (int counter = s.readInt() - 1; counter >= 0; counter--) {
	put((KeyStroke)s.readObject(), s.readObject());
	}
	}
	}

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