/*
 * Copyright (c) 1999, 2011, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
 *
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 */
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());
 }
 }
}