/*
* @(#)Component.java 1.450 09/04/13
*
* Copyright 2008 Sun Microsystems, Inc. All rights reserved.
* SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
*/
package java.awt;
import java.io.PrintStream;
import java.io.PrintWriter;
import java.util.Vector;
import java.util.Locale;
import java.util.EventListener;
import java.util.Iterator;
import java.util.HashSet;
import java.util.Map;
import java.util.Set;
import java.util.Collections;
import java.awt.peer.ComponentPeer;
import java.awt.peer.ContainerPeer;
import java.awt.peer.LightweightPeer;
import java.awt.image.BufferStrategy;
import java.awt.image.ImageObserver;
import java.awt.image.ImageProducer;
import java.awt.image.ColorModel;
import java.awt.image.VolatileImage;
import java.awt.event.*;
import java.awt.datatransfer.Transferable;
import java.awt.dnd.DnDConstants;
import java.awt.dnd.DragSource;
import java.awt.dnd.DragSourceContext;
import java.awt.dnd.DragSourceListener;
import java.awt.dnd.InvalidDnDOperationException;
import java.io.Serializable;
import java.io.ObjectOutputStream;
import java.io.ObjectInputStream;
import java.io.IOException;
import java.beans.PropertyChangeListener;
import java.beans.PropertyChangeSupport;
import java.awt.event.InputMethodListener;
import java.awt.event.InputMethodEvent;
import java.awt.im.InputContext;
import java.awt.im.InputMethodRequests;
import java.awt.dnd.DropTarget;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import javax.accessibility.*;
import java.awt.GraphicsConfiguration;
import java.security.AccessController;
import java.security.PrivilegedAction;
import javax.accessibility.*;
import java.lang.ref.*;
import java.util.logging.*;
import java.applet.Applet;
import sun.security.action.GetPropertyAction;
import sun.awt.AppContext;
import sun.awt.AWTAccessor;
import sun.awt.SunToolkit;
import sun.awt.ConstrainableGraphics;
import sun.awt.DebugHelper;
import sun.awt.SubRegionShowable;
import sun.awt.WindowClosingListener;
import sun.awt.WindowClosingSupport;
import sun.awt.GlobalCursorManager;
import sun.awt.CausedFocusEvent;
import sun.awt.EmbeddedFrame;
import sun.awt.dnd.SunDropTargetEvent;
import sun.awt.im.CompositionArea;
import sun.awt.image.VSyncedBSManager;
import sun.java2d.SunGraphics2D;
import sun.java2d.SunGraphicsEnvironment;
import sun.java2d.pipe.Region;
import sun.java2d.pipe.hw.ExtendedBufferCapabilities;
import static sun.java2d.pipe.hw.ExtendedBufferCapabilities.VSyncType.*;
import sun.awt.RequestFocusController;
/**
* A <em>component</em> is an object having a graphical representation
* that can be displayed on the screen and that can interact with the
* user. Examples of components are the buttons, checkboxes, and scrollbars
* of a typical graphical user interface. <p>
* The <code>Component</code> class is the abstract superclass of
* the nonmenu-related Abstract Window Toolkit components. Class
* <code>Component</code> can also be extended directly to create a
* lightweight component. A lightweight component is a component that is
* not associated with a native opaque window.
* <p>
* <h3>Serialization</h3>
* It is important to note that only AWT listeners which conform
* to the <code>Serializable</code> protocol will be saved when
* the object is stored. If an AWT object has listeners that
* aren't marked serializable, they will be dropped at
* <code>writeObject</code> time. Developers will need, as always,
* to consider the implications of making an object serializable.
* One situation to watch out for is this:
* <pre>
* import java.awt.*;
* import java.awt.event.*;
* import java.io.Serializable;
*
* class MyApp implements ActionListener, Serializable
* {
* BigObjectThatShouldNotBeSerializedWithAButton bigOne;
* Button aButton = new Button();
*
* MyApp()
* {
* // Oops, now aButton has a listener with a reference
* // to bigOne!
* aButton.addActionListener(this);
* }
*
* public void actionPerformed(ActionEvent e)
* {
* System.out.println("Hello There");
* }
* }
* </pre>
* In this example, serializing <code>aButton</code> by itself
* will cause <code>MyApp</code> and everything it refers to
* to be serialized as well. The problem is that the listener
* is serializable by coincidence, not by design. To separate
* the decisions about <code>MyApp</code> and the
* <code>ActionListener</code> being serializable one can use a
* nested class, as in the following example:
* <pre>
* import java.awt.*;
* import java.awt.event.*;
* import java.io.Serializable;
*
* class MyApp java.io.Serializable
* {
* BigObjectThatShouldNotBeSerializedWithAButton bigOne;
* Button aButton = new Button();
*
* static class MyActionListener implements ActionListener
* {
* public void actionPerformed(ActionEvent e)
* {
* System.out.println("Hello There");
* }
* }
*
* MyApp()
* {
* aButton.addActionListener(new MyActionListener());
* }
* }
* </pre>
* <p>
* <b>Note</b>: For more information on the paint mechanisms utilitized
* by AWT and Swing, including information on how to write the most
* efficient painting code, see
* <a href="http://java.sun.com/products/jfc/tsc/articles/painting/index.html">Painting in AWT and Swing</a>.
* <p>
* For details on the focus subsystem, see
* <a href="http://java.sun.com/docs/books/tutorial/uiswing/misc/focus.html">
* How to Use the Focus Subsystem</a>,
* a section in <em>The Java Tutorial</em>, and the
* <a href="../../java/awt/doc-files/FocusSpec.html">Focus Specification</a>
* for more information.
*
* @version 1.450, 04/13/09
* @author Arthur van Hoff
* @author Sami Shaio
*/
public abstract class Component implements ImageObserver, MenuContainer,
Serializable
{
private static final Logger focusLog = Logger.getLogger("java.awt.focus.Component");
private static final Logger log = Logger.getLogger("java.awt.Component");
private static final Logger mixingLog = Logger.getLogger("java.awt.mixing.Component");
/**
* The peer of the component. The peer implements the component's
* behavior. The peer is set when the <code>Component</code> is
* added to a container that also is a peer.
* @see #addNotify
* @see #removeNotify
*/
transient ComponentPeer peer;
/**
* The parent of the object. It may be <code>null</code>
* for top-level components.
* @see #getParent
*/
transient Container parent;
/**
* The <code>AppContext</code> of the component. Applets/Plugin may
* change the AppContext.
*/
transient AppContext appContext;
/**
* The x position of the component in the parent's coordinate system.
*
* @serial
* @see #getLocation
*/
int x;
/**
* The y position of the component in the parent's coordinate system.
*
* @serial
* @see #getLocation
*/
int y;
/**
* The width of the component.
*
* @serial
* @see #getSize
*/
int width;
/**
* The height of the component.
*
* @serial
* @see #getSize
*/
int height;
/**
* The foreground color for this component.
* <code>foreground</code> can be <code>null</code>.
*
* @serial
* @see #getForeground
* @see #setForeground
*/
Color foreground;
/**
* The background color for this component.
* <code>background</code> can be <code>null</code>.
*
* @serial
* @see #getBackground
* @see #setBackground
*/
Color background;
/**
* The font used by this component.
* The <code>font<
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