/*
* Copyright (c) 1999, 2014, 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} provides a binding between an input event (currently only
* {@code KeyStroke}s are used) and an {@code Object}. {@code InputMap}s are
* usually used with an {@code ActionMap}, to determine an {@code Action} to
* perform when a key is pressed. An {@code InputMap} can have a parent that
* is searched for bindings not defined in the {@code InputMap}.
* <p>As with {@code ActionMap} 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} with no parent and no mappings.
*/
public InputMap() {
}
/**
* Sets this {@code InputMap}'s parent.
*
* @param map the {@code InputMap} that is the parent of this one
*/
public void setParent(InputMap map) {
this.parent = map;
}
/**
* Gets this {@code InputMap}'s parent.
*
* @return map the {@code InputMap} that is the parent of this one,
* or null if this {@code InputMap} has no parent
*/
public InputMap getParent() {
return parent;
}
/**
* Adds a binding for {@code keyStroke} to {@code actionMapKey}.
* If {@code actionMapKey} is null, this removes the current binding
* for {@code keyStroke}.
*
* @param keyStroke a {@code KeyStroke}
* @param actionMapKey an action map key
*/
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}, messaging the
* parent {@code InputMap} if the binding is not locally defined.
*
* @param keyStroke the {@code KeyStroke} for which to get the binding
* @return the binding for {@code keyStroke}
*/
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} from this {@code InputMap}.
*
* @param key the {@code KeyStroke} for which to remove the binding
*/
public void remove(KeyStroke key) {
if (arrayTable != null) {
arrayTable.remove(key);
}
}
/**
* Removes all the mappings from this {@code InputMap}.
*/
public void clear() {
if (arrayTable != null) {
arrayTable.clear();
}
}
/**
* Returns the {@code KeyStroke}s that are bound in this {@code InputMap}.
*
* @return an array of the {@code KeyStroke}s that are bound in this
* {@code InputMap}
*/
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} bindings.
*
* @return the number of {@code KeyStroke} bindings
*/
public int size() {
if (arrayTable == null) {
return 0;
}
return arrayTable.size();
}
/**
* Returns an array of the {@code KeyStroke}s defined in this
* {@code InputMap} and its parent. This differs from {@code keys()}
* in that this method includes the keys defined in the parent.
*
* @return an array of the {@code KeyStroke}s defined in this
* {@code InputMap} and its 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());
}
}
}