Java tutorial
/* * Copyright (c) 1997, 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.event; import java.awt.event.*; import java.awt.*; import javax.swing.*; /** * An event reported to a child component that originated from an * ancestor in the component hierarchy. * <p> * <strong>Warning:</strong> * Serialized objects of this class will not be compatible with * future Swing releases. The current serialization support is * appropriate for short term storage or RMI between applications running * the same version of Swing. As of 1.4, support for long term storage * of all JavaBeans™ * has been added to the <code>java.beans</code> package. * Please see {@link java.beans.XMLEncoder}. * * @author Dave Moore */ @SuppressWarnings("serial") public class AncestorEvent extends AWTEvent { /** * An ancestor-component was added to the hierarchy of * visible objects (made visible), and is currently being displayed. */ public static final int ANCESTOR_ADDED = 1; /** * An ancestor-component was removed from the hierarchy * of visible objects (hidden) and is no longer being displayed. */ public static final int ANCESTOR_REMOVED = 2; /** An ancestor-component changed its position on the screen. */ public static final int ANCESTOR_MOVED = 3; Container ancestor; Container ancestorParent; /** * Constructs an AncestorEvent object to identify a change * in an ancestor-component's display-status. * * @param source the JComponent that originated the event * (typically <code>this</code>) * @param id an int specifying {@link #ANCESTOR_ADDED}, * {@link #ANCESTOR_REMOVED} or {@link #ANCESTOR_MOVED} * @param ancestor a Container object specifying the ancestor-component * whose display-status changed * @param ancestorParent a Container object specifying the ancestor's parent */ public AncestorEvent(JComponent source, int id, Container ancestor, Container ancestorParent) { super(source, id); this.ancestor = ancestor; this.ancestorParent = ancestorParent; } /** * Returns the ancestor that the event actually occurred on. * * @return the {@code Container} object specifying the ancestor component */ public Container getAncestor() { return ancestor; } /** * Returns the parent of the ancestor the event actually occurred on. * This is most interesting in an ANCESTOR_REMOVED event, as * the ancestor may no longer be in the component hierarchy. * * @return the {@code Container} object specifying the ancestor's parent */ public Container getAncestorParent() { return ancestorParent; } /** * Returns the component that the listener was added to. * * @return the {@code JComponent} on which the event occurred */ public JComponent getComponent() { return (JComponent) getSource(); } }