Java tutorial
/* * 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; /** * A <code>ComponentInputMap</code> is an <code>InputMap</code> * associated with a particular <code>JComponent</code>. * The component is automatically notified whenever * the <code>ComponentInputMap</code> changes. * <code>ComponentInputMap</code>s are used for * <code>WHEN_IN_FOCUSED_WINDOW</code> bindings. * * @author Scott Violet * @since 1.3 */ @SuppressWarnings("serial") // Field data not serializable across versions public class ComponentInputMap extends InputMap { /** Component binding is created for. */ private JComponent component; /** * Creates a <code>ComponentInputMap</code> associated with the * specified component. * * @param component a non-null <code>JComponent</code> * @throws IllegalArgumentException if <code>component</code> is null */ public ComponentInputMap(JComponent component) { this.component = component; if (component == null) { throw new IllegalArgumentException("ComponentInputMaps must be associated with a non-null JComponent"); } } /** * Sets the parent, which must be a <code>ComponentInputMap</code> * associated with the same component as this * <code>ComponentInputMap</code>. * * @param map a <code>ComponentInputMap</code> * * @throws IllegalArgumentException if <code>map</code> * is not a <code>ComponentInputMap</code> * or is not associated with the same component */ public void setParent(InputMap map) { if (getParent() == map) { return; } if (map != null && (!(map instanceof ComponentInputMap) || ((ComponentInputMap) map).getComponent() != getComponent())) { throw new IllegalArgumentException( "ComponentInputMaps must have a parent ComponentInputMap associated with the same component"); } super.setParent(map); getComponent().componentInputMapChanged(this); } /** * Returns the component the {@code InputMap} was created for. * * @return the component the {@code InputMap} was created for. */ public JComponent getComponent() { return component; } /** * 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) { super.put(keyStroke, actionMapKey); if (getComponent() != null) { getComponent().componentInputMapChanged(this); } } /** * Removes the binding for <code>key</code> from this object. */ public void remove(KeyStroke key) { super.remove(key); if (getComponent() != null) { getComponent().componentInputMapChanged(this); } } /** * Removes all the mappings from this object. */ public void clear() { int oldSize = size(); super.clear(); if (oldSize > 0 && getComponent() != null) { getComponent().componentInputMapChanged(this); } } }