/*
 * @(#)Window.java	1.184 03/01/28
 *
 * Copyright 2003 Sun Microsystems, Inc. All rights reserved.
 * SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 */
package java.awt;

import java.applet.Applet;
import java.awt.peer.WindowPeer;
import java.awt.event.*;
import java.awt.image.BufferStrategy;
import java.util.Vector;
import java.util.Locale;
import java.util.EventListener;
import java.util.Set;
import java.io.Serializable;
import java.io.ObjectOutputStream;
import java.io.ObjectInputStream;
import java.io.IOException;
import java.io.OptionalDataException;
import java.awt.im.InputContext;
import java.util.ResourceBundle;
import java.lang.ref.WeakReference;
import java.lang.reflect.InvocationTargetException;
import java.security.AccessController;
import java.security.PrivilegedAction;
import javax.accessibility.*;
import java.beans.PropertyChangeListener;
import sun.security.action.GetPropertyAction;
import sun.awt.DebugHelper;

/**
 * A <code>Window</code> object is a top-level window with no borders and no
 * menubar.  
 * The default layout for a window is <code>BorderLayout</code>.
 * <p>
 * A window must have either a frame, dialog, or another window defined as its
 * owner when it's constructed. 
 * <p>
 * In a multi-screen environment, you can create a <code>Window</code>
 * on a different screen device by constructing the <code>Window</code>
 * with {@link #Window(Window, GraphicsConfiguration)}.  The 
 * <code>GraphicsConfiguration</code> object is one of the 
 * <code>GraphicsConfiguration</code> objects of the target screen device.  
 * <p>
 * In a virtual device multi-screen environment in which the desktop 
 * area could span multiple physical screen devices, the bounds of all
 * configurations are relative to the virtual device coordinate system.  
 * The origin of the virtual-coordinate system is at the upper left-hand 
 * corner of the primary physical screen.  Depending on the location of
 * the primary screen in the virtual device, negative coordinates are 
 * possible, as shown in the following figure.
 * <p>
 * <img src="doc-files/MultiScreen.gif"
 * alt="Diagram shows virtual device containing 4 physical screens. Primary physical screen shows coords (0,0), other screen shows (-80,-100)."
 * ALIGN=center HSPACE=10 VSPACE=7>
 * <p>  
 * In such an environment, when calling <code>setLocation</code>, 
 * you must pass a virtual coordinate to this method.  Similarly,
 * calling <code>getLocationOnScreen</code> on a <code>Window</code> returns 
 * virtual device coordinates.  Call the <code>getBounds</code> method 
 * of a <code>GraphicsConfiguration</code> to find its origin in the virtual
 * coordinate system.
 * <p>
 * The following code sets the location of a <code>Window</code> 
 * at (10, 10) relative to the origin of the physical screen
 * of the corresponding <code>GraphicsConfiguration</code>.  If the 
 * bounds of the <code>GraphicsConfiguration</code> is not taken 
 * into account, the <code>Window</code> location would be set 
 * at (10, 10) relative to the virtual-coordinate system and would appear
 * on the primary physical screen, which might be different from the
 * physical screen of the specified <code>GraphicsConfiguration</code>.
 *
 * <pre>
 *	Window w = new Window(Window owner, GraphicsConfiguration gc);
 *	Rectangle bounds = gc.getBounds();
 *	w.setLocation(10 + bounds.x, 10 + bounds.y);
 * </pre>
 *
 * <p>
 * Windows are capable of generating the following WindowEvents:
 * WindowOpened, WindowClosed, WindowGainedFocus, WindowLostFocus.
 *
 * @version 	1.184, 01/28/03
 * @author 	Sami Shaio
 * @author 	Arthur van Hoff
 * @see WindowEvent
 * @see #addWindowListener
 * @see java.awt.BorderLayout
 * @since       JDK1.0
 */
public class Window extends Container implements Accessible {

    /**
     * This represents the warning message that is
     * to be displayed in a non secure window. ie :
     * a window that has a security manager installed for
     * which calling SecurityManager.checkTopLevelWindow()
     * is false.  This message can be displayed anywhere in
     * the window.
     *
     * @serial
     * @see #getWarningString
     */
    String      warningString;

    /**
     * Holds the reference to the component which last had focus in this window
     * before it lost focus.
     */
    private transient Component temporaryLostComponent;

    static boolean systemSyncLWRequests = false;
    boolean     syncLWRequests = false;
    transient boolean beforeFirstShow = true;

    static final int OPENED = 0x01;

    /**
     * An Integer value representing the Window State.
     *
     * @serial
     * @since 1.2
     * @see #show
     */
    int state;

    /**
     * A vector containing all the windows this
     * window currently owns.
     * @since 1.2
     * @see #getOwnedWindows
     */
    transient Vector ownedWindowList = new Vector();
    private transient WeakReference weakThis;

    private transient boolean showWithParent = false;
    
    transient WindowListener windowListener;
    transient WindowStateListener windowStateListener;
    transient WindowFocusListener windowFocusListener;

    transient InputContext inputContext;
    private transient Object inputContextLock = new Object();

    /**
     * Unused. Maintained for serialization backward-compatibility.
     *
     * @serial
     * @since 1.2
     */
    private FocusManager focusMgr;

    /**
     * Indicates whether this Window can become the focused Window.
     *
     * @serial
     * @see #getFocusableWindowState
     * @see #setFocusableWindowState
     * @since 1.4
     */
    private boolean focusableWindowState = true;

    private static final String base = "win";
    private static int nameCounter = 0;

    /*
     * JDK 1.1 serialVersionUID 
     */
    private static final long serialVersionUID = 4497834738069338734L;

    private static final DebugHelper dbg = DebugHelper.create(Window.class);

    static {
        /* ensure that the necessary native libraries are loaded */
	Toolkit.loadLibraries();
        if (!GraphicsEnvironment.isHeadless()) {
            initIDs();
        }
 systemSyncLWRequests = ((Boolean)AccessController.doPrivileged(
     new PrivilegedAction() {
                    public Object run() {
                        return new Boolean("true".equals(System.
                                                         getProperty("java.awt.syncLWRequests",
                                                                     "false")));
                    }
                })).booleanValue();
    }

    /**
     * Initialize JNI field and method IDs for fields that may be
       accessed from C.
     */
    private static native void initIDs();

    /**
     * Constructs a new window in default size with the 
     * specified <code>GraphicsConfiguration</code>.
     * <p>
     * If there is a security manager, this method first calls 
     * the security manager's <code>checkTopLevelWindow</code> 
     * method with <code>this</code> 
     * as its argument to determine whether or not the window 
     * must be displayed with a warning banner. 
     * @param gc the <code>GraphicsConfiguration</code>
     * of the target screen device.  If <code>gc</code> is
     * <code>null</code>, the system default
     * <code>GraphicsConfiguration</code> is assumed.
     * @exception IllegalArgumentException if <code>gc</code>
     * is not from a screen device.  This exception is always
     * thrown when GraphicsEnvironment.isHeadless() returns true.
     * @see java.awt.GraphicsEnvironment#isHeadless
     * @see java.lang.SecurityManager#checkTopLevelWindow 
     */
    Window(GraphicsConfiguration gc) {
        init(gc);
    }

    private void init(GraphicsConfiguration gc) {
        if (GraphicsEnvironment.isHeadless()) {
            throw new IllegalArgumentException("headless environment");
        }

        syncLWRequests = systemSyncLWRequests;

	setWarningString();
	this.cursor = Cursor.getPredefinedCursor(Cursor.DEFAULT_CURSOR);
	this.visible = false;
        if (gc == null) {
            this.graphicsConfig =
                GraphicsEnvironment.getLocalGraphicsEnvironment().
             getDefaultScreenDevice().getDefaultConfiguration();
        } else {
            this.graphicsConfig = gc;
        }
        if (graphicsConfig.getDevice().getType() !=
            GraphicsDevice.TYPE_RASTER_SCREEN) {
            throw new IllegalArgumentException("not a screen device");
        }
	setLayout(new BorderLayout());

        /* offset the initial location with the original of the screen */
        /* and any insets                                              */
        Rectangle screenBounds = graphicsConfig.getBounds();
        Insets screenInsets = getToolkit().getScreenInsets(graphicsConfig);          
        int x = getX() + screenBounds.x + screenInsets.left;
        int y = getY() + screenBounds.y + screenInsets.top;
        setLocation(x, y);
    }
    
    /**
     * Constructs a new window in the default size.
     * 
     * <p>First, if there is a security manager, its 
     * <code>checkTopLevelWindow</code> 
     * method is called with <code>this</code> 
     * as its argument
     * to see if it's ok to display the window without a warning banner. 
     * If the default implementation of <code>checkTopLevelWindow</code> 
     * is used (that is, that method is not overriden), then this results in
     * a call to the security manager's <code>checkPermission</code> method
     * with an <code>AWTPermission("showWindowWithoutWarningBanner")</code>
     * permission. It that method raises a SecurityException, 
     * <code>checkTopLevelWindow</code> returns false, otherwise it
     * returns true. If it returns false, a warning banner is created.
     *
     * @exception HeadlessException if GraphicsEnvironment.isHeadless()
     * returns true
     * @see java.awt.GraphicsEnvironment#isHeadless
     * @see java.lang.SecurityManager#checkTopLevelWindow
     */
    Window() throws HeadlessException {
        GraphicsEnvironment.checkHeadless();
        init((GraphicsConfiguration)null);
    }
    
    /**
     * Constructs a new invisible window with the specified
     * <code>Frame</code> as its owner. The Window will not be focusable 
     * unless its owner is showing on the screen.
     * <p>
     * If there is a security manager, this method first calls 
     * the security manager's <code>checkTopLevelWindow</code> 
     * method with <code>this</code> 
     * as its argument to determine whether or not the window 
     * must be displayed with a warning banner. 
     * 
     * @param owner the <code>Frame</code> to act as owner
     * @exception IllegalArgumentException if the <code>owner</code>'s
     *    <code>GraphicsConfiguration</code> is not from a screen device
     * @exception java.lang.IllegalArgumentException if 
     *    <code>owner</code> is <code>null</code> this exception
     *    is always thrown when <code>GraphicsEnvironment.isHeadless</code>
     *    returns true
     * @see java.awt.GraphicsEnvironment#isHeadless
     * @see java.lang.SecurityManager#checkTopLevelWindow
     * @see #isShowing
     */
    public Window(Frame owner) {
        this(owner == null ? (GraphicsConfiguration)null :
            owner.getGraphicsConfiguration());
	ownedInit(owner);
    }

    /**
     * Constructs a new invisible window with the specified
     * <code>Window</code> as its owner. The Window will not be focusable 
     * unless its nearest owning Frame or Dialog is showing on the screen.
     * <p>
     * If there is a security manager, this method first calls 
     * the security manager's <code>checkTopLevelWindow</code> 
     * method with <code>this</code> 
     * as its argument to determine whether or not the window 
     * must be displayed with a warning banner. 
     * 
     * @param     owner   the <code>Window</code> to act as owner
     * @exception IllegalArgumentException if the <code>owner</code>'s
     *    <code>GraphicsConfiguration</code> is not from a screen device
     * @exception java.lang.IllegalArgumentException if <code>owner</code> 
     *            is <code>null</code>.  This exception is always thrown
     *            when GraphicsEnvironment.isHeadless() returns true.
     * @see       java.awt.GraphicsEnvironment#isHeadless
     * @see       java.lang.SecurityManager#checkTopLevelWindow
     * @see       #isShowing
     * @since     1.2
     */
    public Window(Window owner) {
        this(owner == null ? (GraphicsConfiguration)null :
            owner.getGraphicsConfiguration());
	ownedInit(owner);
    }

    /**
     * Constructs a new invisible window with the specified
     * window as its owner and a 
     * <code>GraphicsConfiguration</code> of a screen device. The Window will
     * not be focusable unless its nearest owning Frame or Dialog is showing on
     * the screen.
     * <p>
     * If there is a security manager, this method first calls 
     * the security manager's <code>checkTopLevelWindow</code> 
     * method with <code>this</code> 
     * as its argument to determine whether or not the window 
     * must be displayed with a warning banner.
     *
     * @param     owner   the window to act as owner
     * @param gc the <code>GraphicsConfiguration</code>
     *   of the target screen device; if <code>gc</code> is 
     *   <code>null</code>, the system default 
     *   <code>GraphicsConfiguration</code> is assumed
     * @throws IllegalArgumentException if
     *            <code>owner</code> is <code>null</code>
     * @throws IllegalArgumentException if <code>gc</code> is not from
     *   a screen device; this exception is always thrown when
     *   <code>GraphicsEnvironment.isHeadless</code> returns
     *   <code>true</code>
     * @see       java.awt.GraphicsEnvironment#isHeadless
     * @see       java.lang.SecurityManager#checkTopLevelWindow
     * @see       GraphicsConfiguration#getBounds
     * @see       #isShowing
     * @since     1.3
     */
    public Window(Window owner, GraphicsConfiguration gc) {
        this(gc);
	ownedInit(owner);
    }

    private void ownedInit(Window owner) {
	if (owner == null) {
	    throw new IllegalArgumentException("null owner window");
	}	
	this.parent = owner;
	this.weakThis = new WeakReference(this);
	owner.addOwnedWindow(weakThis);
    }

    /**
     * Disposes of the input methods and context, and removes the WeakReference
     * which formerly pointed to this Window from the parent's owned Window
     * list.
     */
    protected void finalize() throws Throwable {
	if (parent != null) {
	    ((Window)parent).removeOwnedWindow(weakThis);
	}
	super.finalize();
    }

    /**
     * Construct a name for this component.  Called by getName() when the
     * name is null.
     */
    String constructComponentName() {
        synchronized (getClass()) {
	    return base + nameCounter++;
	}
    }

    /**
     * Makes this Window displayable by creating the connection to its
     * native screen resource.  
     * This method is called internally by the toolkit and should
     * not be called directly by programs.
     * @see Component#isDisplayable
     * @see Container#removeNotify
     * @since JDK1.0
     */
    public void addNotify() {
	synchronized (getTreeLock()) {
	    Container parent = this.parent;
	    if (parent != null && parent.getPeer() == null) {
	        parent.addNotify();
	    }

	    if (peer == null)
		peer = getToolkit().createWindow(this);
	    super.addNotify();
	}
    }

    /**
     * Causes this Window to be sized to fit the preferred size
     * and layouts of its subcomponents.  If the window and/or its owner
     * are not yet displayable, both are made displayable before
     * calculating the preferred size.  The Window will be validated
     * after the preferredSize is calculated.
     * @see Component#isDisplayable
     */
    public void pack() {
	Container parent = this.parent;
	if (parent != null && parent.getPeer() == null) {
	    parent.addNotify();
	}
	if (peer == null) {
	    addNotify();
	}
	setSize(getPreferredSize());

        if(beforeFirstShow) {
            isPacked = true;
        }

	validate();
    }

    /**
     * Makes the Window visible. If the Window and/or its owner
     * are not yet displayable, both are made displayable.  The 
     * Window will be validated prior to being made visible.  
     * If the Window is already visible, this will bring the Window 
     * to the front.
     * @see       Component#isDisplayable
     * @see       #toFront
     * @see       Component#setVisible
     */
    public void show() {
	if (peer == null) {
	    addNotify();
	}
	validate();

	if (visible) {
	    toFront();
	} else {
            beforeFirstShow = false;
	    super.show();
	    for (int i = 0; i < ownedWindowList.size(); i++) {
                Window child = (Window) (((WeakReference)
                    (ownedWindowList.elementAt(i))).get());
                        if ((child != null) && child.showWithParent) {
                            child.show();
                            child.showWithParent = false;
                        }       // endif
            }   // endfor

	}
        
        // If first time shown, generate WindowOpened event
        if ((state & OPENED) == 0) {
            postWindowEvent(WindowEvent.WINDOW_OPENED);
            state |= OPENED;
        }
    }

    synchronized void postWindowEvent(int id) {
        if (windowListener != null
            || (eventMask & AWTEvent.WINDOW_EVENT_MASK) != 0
            ||  Toolkit.enabledOnToolkit(AWTEvent.WINDOW_EVENT_MASK)) {
            WindowEvent e = new WindowEvent(this, id);
            Toolkit.getEventQueue().postEvent(e);
        }
    }

    /**
     * Hide this Window, its subcomponents, and all of its owned children. 
     * The Window and its subcomponents can be made visible again
     * with a call to <code>show</code>. 
     * </p>
     * @see #show
     * @see #dispose
     */
    public void hide() {
        synchronized(ownedWindowList) {
	    for (int i = 0; i < ownedWindowList.size(); i++) {
	        Window child = (Window) (((WeakReference)
		    (ownedWindowList.elementAt(i))).get());
		if ((child != null) && child.visible) {
                    child.hide();
                    child.showWithParent = true;
                }
	    }
	}
	super.hide();
    }

    final void clearMostRecentFocusOwnerOnHide() {
        /* do nothing */
    }
    /**
     * Releases all of the native screen resources used by this
     * <code>Window</code>, its subcomponents, and all of its owned
     * children. That is, the resources for these <code>Component</code>s
     * will be destroyed, any memory they consume will be returned to the
     * OS, and they will be marked as undisplayable.
     * <p>
     * The <code>Window</code> and its subcomponents can be made displayable
     * again by rebuilding the native resources with a subsequent call to
     * <code>pack</code> or <code>show</code>. The states of the recreated
     * <code>Window</code> and its subcomponents will be identical to the
     * states of these objects at the point where the <code>Window</code>
     * was disposed (not accounting for additional modifications between
     * those actions).
     * <p>
     * <b>Note</b>: When the last displayable window
     * within the Java virtual machine (VM) is disposed of, the VM may
     * terminate.  See <a href="doc-files/AWTThreadIssues.html">
     * AWT Threading Issues</a> for more information.
     * @see Component#isDisplayable
     * @see #pack
     * @see #show
     */
    public void dispose() {
    class DisposeAction implements Runnable {
        public void run() {
            synchronized(ownedWindowList) {
                for (int i = 0; i < ownedWindowList.size(); i++) {
                    Window child = (Window) (((WeakReference)
                                   (ownedWindowList.elementAt(i))).get());
                    if (child != null) {
                        child.dispose();
                    }
                }
            }
            setVisible(false);
            beforeFirstShow = true;
            removeNotify();
            synchronized (inputContextLock) {
                if (inputContext != null) {
                    inputContext.dispose();
                    inputContext = null;
                }
            }
            clearCurrentFocusCycleRootOnHide();
        }
    }

	DisposeAction action = new DisposeAction();
	if (EventQueue.isDispatchThread()) {
	    action.run();
	}
	else {
	    try {
	        EventQueue.invokeAndWait(action);
	    }
	    catch (InterruptedException e) {
	        System.err.println("Disposal was interrupted:");
		e.printStackTrace();
	    }
	    catch (InvocationTargetException e) {
	        System.err.println("Exception during disposal:");
		e.printStackTrace();
	    }
	}
	// Execute outside the Runnable because postWindowEvent is
	// synchronized on (this). We don't need to synchronize the call
	// on the EventQueue anyways.
	postWindowEvent(WindowEvent.WINDOW_CLOSED);
    }

    /*
     * Should only be called while holding the tree lock.
     * It's overridden here because parent == owner in Window,
     * and we shouldn't adjust counter on owner
     */
    void adjustListeningChildrenOnParent(long mask, int num) {
    }

    // Should only be called while holding tree lock
    void adjustDecendantsOnParent(int num) {
        // do nothing since parent == owner and we shouldn't 
        // ajust counter on owner
    }

    /**
     * If this Window is visible, brings this Window to the front and may make
     * it the focused Window.
     * <p>
     * Places this Window at the top of the stacking order and shows it in
     * front of any other Windows in this VM. No action will take place if this
     * Window is not visible. Some platforms do not allow Windows which own
     * other Windows to appear on top of those owned Windows. Some platforms
     * may not permit this VM to place its Windows above windows of native
     * applications, or Windows of other VMs. This permission may depend on
     * whether a Window in this VM is already focused. Every attempt will be
     * made to move this Window as high as possible in the stacking order;
     * however, developers should not assume that this method will move this
     * Window above all other windows in every situation.
     * <p>
     * Because of variations in native windowing systems, no guarantees about
     * changes to the focused and active Windows can be made. Developers must
     * never assume that this Window is the focused or active Window until this
     * Window receives a WINDOW_GAINED_FOCUS or WINDOW_ACTIVATED event. On
     * platforms where the top-most window is the focused window, this method
     * will <b>probably</b> focus this Window, if it is not already focused. On
     * platforms where the stacking order does not typically affect the focused
     * window, this method will <b>probably</b> leave the focused and active
     * Windows unchanged.
     * <p>
     * If this method causes this Window to be focused, and this Window is a
     * Frame or a Dialog, it will also become activated. If this Window is
     * focused, but it is not a Frame or a Dialog, then the first Frame or
     * Dialog that is an owner of this Window will be activated.
     *
     * @see       #toBack
     */
    public void toFront() {
        if (visible) {
	    WindowPeer peer = (WindowPeer)this.peer;
	    if (peer != null) {
	        peer.toFront();
	    }
	}
    }

    /**
     * If this Window is visible, sends this Window to the back and may cause
     * it to lose focus or activation if it is the focused or active Window.
     * <p>
     * Places this Window at the bottom of the stacking order and shows it
     * behind any other Windows in this VM. No action will take place is this
     * Window is not visible. Some platforms do not allow Windows which are
     * owned by other Windows to appear below their owners. Every attempt will
     * be made to move this Window as low as possible in the stacking order;
     * however, developers should not assume that this method will move this
     * Window below all other windows in every situation.
     * <p>
     * Because of variations in native windowing systems, no guarantees about
     * changes to the focused and active Windows can be made. Developers must
     * never assume that this Window is no longer the focused or active Window
     * until this Window receives a WINDOW_LOST_FOCUS or WINDOW_DEACTIVATED
     * event. On platforms where the top-most window is the focused window,
     * this method will <b>probably</b> cause this Window to lose focus. In
     * that case, the next highest, focusable Window in this VM will receive
     * focus. On platforms where the stacking order does not typically affect
     * the focused window, this method will <b>probably</b> leave the focused
     * and active Windows unchanged.
     *
     * @see       #toFront
     */
    public void toBack() {
        if (visible) {
	    WindowPeer peer = (WindowPeer)this.peer;
	    if (peer != null) {
	        peer.toBack();
	    }
	}
    }

    /**
     * Returns the toolkit of this frame.
     * @return    the toolkit of this window.
     * @see       Toolkit
     * @see       Toolkit#getDefaultToolkit
     * @see       Component#getToolkit
     */
    public Toolkit getToolkit() {
	return Toolkit.getDefaultToolkit();
    }

    /**
     * Gets the warning string that is displayed with this window. 
     * If this window is insecure, the warning string is displayed 
     * somewhere in the visible area of the window. A window is 
     * insecure if there is a security manager, and the security 
     * manager's <code>checkTopLevelWindow</code> method returns 
     * <code>false</code> when this window is passed to it as an
     * argument.
     * <p>
     * If the window is secure, then <code>getWarningString</code>
     * returns <code>null</code>. If the window is insecure, this
     * method checks for the system property 
     * <code>awt.appletWarning</code> 
     * and returns the string value of that property. 
     * @return    the warning string for this window.
     * @see       java.lang.SecurityManager#checkTopLevelWindow(java.lang.Object)
     */
    public final String getWarningString() {
	return warningString;
    }

    private void setWarningString() {
	warningString = null;
	SecurityManager sm = System.getSecurityManager();
	if (sm != null) {
	    if (!sm.checkTopLevelWindow(this)) {
		// make sure the privileged action is only
		// for getting the property! We don't want the
		// above checkTopLevelWindow call to always succeed!
		warningString = (String) AccessController.doPrivileged(
		      new GetPropertyAction("awt.appletWarning",
					    "Java Applet Window"));
	    }
	}
    }

    /** 
     * Gets the <code>Locale</code> object that is associated 
     * with this window, if the locale has been set.
     * If no locale has been set, then the default locale 
     * is returned.
     * @return    the locale that is set for this window.
     * @see       java.util.Locale
     * @since     JDK1.1
     */

    public Locale getLocale() {
      if (this.locale == null) {
	return Locale.getDefault();
      }
      return this.locale;
    }

    /**
     * Gets the input context for this window. A window always has an input context,
     * which is shared by subcomponents unless they create and set their own.
     * @see Component#getInputContext
     * @since 1.2
     */

    public InputContext getInputContext() {
        if (inputContext == null) {
            synchronized (inputContextLock) {
                if (inputContext == null) {
                    inputContext = InputContext.getInstance();
                }
            }
        }
        return inputContext;
    }

    /**
     * Set the cursor image to a specified cursor.
     * @param     cursor One of the constants defined
     *            by the <code>Cursor</code> class. If this parameter is null
     *            then the cursor for this window will be set to the type
     *            Cursor.DEFAULT_CURSOR.
     * @see       Component#getCursor
     * @see       Cursor
     * @since     JDK1.1
     */
    public void setCursor(Cursor cursor) {
        if (cursor == null) {
            cursor = Cursor.getPredefinedCursor(Cursor.DEFAULT_CURSOR);
        }
        super.setCursor(cursor);
    }

    /**
     * Returns the owner of this window.
     * @since 1.2
     */
    public Window getOwner() {
        return (Window)parent;
    }

    /**
     * Return an array containing all the windows this
     * window currently owns.
     * @since 1.2
     */
    public Window[] getOwnedWindows() {
        Window realCopy[];

	synchronized(ownedWindowList) {
	    // Recall that ownedWindowList is actually a Vector of
	    // WeakReferences and calling get() on one of these references
	    // may return null. Make two arrays-- one the size of the
	    // Vector (fullCopy with size fullSize), and one the size of 
	    // all non-null get()s (realCopy with size realSize).
	    int fullSize = ownedWindowList.size();
	    int realSize = 0;
	    Window fullCopy[] = new Window[fullSize];

	    for (int i = 0; i < fullSize; i++) {
	        fullCopy[realSize] = (Window) (((WeakReference)
		    (ownedWindowList.elementAt(i))).get());

		if (fullCopy[realSize] != null) {
		    realSize++;
		}
	    }

	    if (fullSize != realSize) {
	        realCopy = new Window[realSize];
		System.arraycopy(fullCopy, 0, realCopy, 0, realSize);
	    } else {
	        realCopy = fullCopy;
	    }
	}

        return realCopy;
    }

    /**
     * Adds the specified window listener to receive window events from
     * this window.
     * If l is null, no exception is thrown and no action is performed.
     *
     * @param 	l the window listener
     * @see #removeWindowListener
     * @see #getWindowListeners
     */ 
    public synchronized void addWindowListener(WindowListener l) {
	if (l == null) {
	    return;
	}
        newEventsOnly = true;
        windowListener = AWTEventMulticaster.add(windowListener, l);
    }

    /**
     * Adds the specified window state listener to receive window
     * events from this window.  If <code>l</code> is </code>null</code>,
     * no exception is thrown and no action is performed.
     *
     * @param   l the window state listener
     * @see #removeWindowStateListener
     * @see #getWindowStateListeners
     * @since 1.4
     */
    public synchronized void addWindowStateListener(WindowStateListener l) {
        if (l == null) {
            return;
        }
        windowStateListener = AWTEventMulticaster.add(windowStateListener, l);
        newEventsOnly = true;
    }

    /**
     * Adds the specified window focus listener to receive window events
     * from this window.
     * If l is null, no exception is thrown and no action is performed.
     *
     * @param   l the window focus listener
     * @see #removeWindowFocusListener
     * @see #getWindowFocusListeners
     */
    public synchronized void addWindowFocusListener(WindowFocusListener l) {
        if (l == null) {
            return;
        }
        windowFocusListener = AWTEventMulticaster.add(windowFocusListener, l);
        newEventsOnly = true;
    }

    /**
     * Removes the specified window listener so that it no longer
     * receives window events from this window.
     * If l is null, no exception is thrown and no action is performed.
     *
     * @param 	l the window listener
     * @see #addWindowListener
     * @see #getWindowListeners
     */ 
    public synchronized void removeWindowListener(WindowListener l) {
	if (l == null) {
	    return;
	}
        windowListener = AWTEventMulticaster.remove(windowListener, l);
    }

    /**
     * Removes the specified window state listener so that it no
     * longer receives window events from this window.  If
     * <code>l</code> is <code>null</code>, no exception is thrown and
     * no action is performed.
     *
     * @param   l the window state listener
     * @see #addWindowStateListener
     * @see #getWindowStateListeners
     * @since 1.4
     */
    public synchronized void removeWindowStateListener(WindowStateListener l) {
        if (l == null) {
            return;
        }
        windowStateListener = AWTEventMulticaster.remove(windowStateListener, l);
    }

    /**
     * Removes the specified window focus listener so that it no longer
     * receives window events from this window.
     * If l is null, no exception is thrown and no action is performed.
     *
     * @param   l the window focus listener
     * @see #addWindowFocusListener
     * @see #getWindowFocusListeners
     */
    public synchronized void removeWindowFocusListener(WindowFocusListener l) {
        if (l == null) {
            return;
        }
        windowFocusListener = AWTEventMulticaster.remove(windowFocusListener, l);
    }

    /**
     * Returns an array of all the window listeners
     * registered on this window.
     *
     * @return all of this window's <code>WindowListener</code>s
     *         or an empty array if no window
     *         listeners are currently registered
     *
     * @see #addWindowListener
     * @see #removeWindowListener
     * @since 1.4
     */
    public synchronized WindowListener[] getWindowListeners() {
        return (WindowListener[])(getListeners(WindowListener.class));
    }

    /**
     * Returns an array of all the window focus listeners
     * registered on this window.
     *
     * @return all of this window's <code>WindowFocusListener</code>s
     *         or an empty array if no window focus
     *         listeners are currently registered
     *
     * @see #addWindowFocusListener
     * @see #removeWindowFocusListener
     * @since 1.4
     */
    public synchronized WindowFocusListener[] getWindowFocusListeners() {
        return (WindowFocusListener[])(getListeners(WindowFocusListener.class));
    }

    /**
     * Returns an array of all the window state listeners
     * registered on this window.
     *
     * @return all of this window's <code>WindowStateListener</code>s
     *         or an empty array if no window state
     *         listeners are currently registered
     *
     * @see #addWindowStateListener
     * @see #removeWindowStateListener
     * @since 1.4
     */
    public synchronized WindowStateListener[] getWindowStateListeners() {
        return (WindowStateListener[])(getListeners(WindowStateListener.class));
    }


    /**
     * Returns an array of all the objects currently registered
     * as <code><em>Foo</em>Listener</code>s
     * upon this <code>Window</code>.
     * <code><em>Foo</em>Listener</code>s are registered using the
     * <code>add<em>Foo</em>Listener</code> method.
     *
     * <p>
     *
     * You can specify the <code>listenerType</code> argument
     * with a class literal, such as
     * <code><em>Foo</em>Listener.class</code>.
     * For example, you can query a
     * <code>Window</code> <code>w</code>
     * for its window listeners with the following code:
     *
     * <pre>WindowListener[] wls = (WindowListener[])(w.getListeners(WindowListener.class));</pre>
     *
     * If no such listeners exist, this method returns an empty array.
     *
     * @param listenerType the type of listeners requested; this parameter
     *          should specify an interface that descends from
     *          <code>java.util.EventListener</code>
     * @return an array of all objects registered as
     *          <code><em>Foo</em>Listener</code>s on this window,
     *          or an empty array if no such
     *          listeners have been added
     * @exception ClassCastException if <code>listenerType</code>
     *          doesn't specify a class or interface that implements
     *          <code>java.util.EventListener</code>
     *
     * @see #getWindowListeners
     * @since 1.3
     */
    public EventListener[] getListeners(Class listenerType) { 
	EventListener l = null; 
        if (listenerType == WindowFocusListener.class) {
            l = windowFocusListener;
	} else if (listenerType == WindowStateListener.class) {
            l = windowStateListener;
        } else if (listenerType == WindowListener.class) {
            l = windowListener;
        } else {
            return super.getListeners(listenerType);
        }
        return (EventListener[])AWTEventMulticaster.getListeners(l, listenerType);
    }

    // REMIND: remove when filtering is handled at lower level
    boolean eventEnabled(AWTEvent e) {
        switch(e.id) {
          case WindowEvent.WINDOW_OPENED:
          case WindowEvent.WINDOW_CLOSING:
          case WindowEvent.WINDOW_CLOSED:
          case WindowEvent.WINDOW_ICONIFIED:
          case WindowEvent.WINDOW_DEICONIFIED:
          case WindowEvent.WINDOW_ACTIVATED:
          case WindowEvent.WINDOW_DEACTIVATED:
            if ((eventMask & AWTEvent.WINDOW_EVENT_MASK) != 0 ||
                windowListener != null) {
                return true;
            }
            return false;
          case WindowEvent.WINDOW_GAINED_FOCUS:
          case WindowEvent.WINDOW_LOST_FOCUS:
            if ((eventMask & AWTEvent.WINDOW_FOCUS_EVENT_MASK) != 0 ||
                windowFocusListener != null) {
                return true;
            }
            return false;
          case WindowEvent.WINDOW_STATE_CHANGED:
            if ((eventMask & AWTEvent.WINDOW_STATE_EVENT_MASK) != 0 ||
                windowStateListener != null) {
                return true;
            }
            return false;
          default:
            break;
        }
        return super.eventEnabled(e);
    }

    /**
     * Processes events on this window. If the event is an
     * <code>WindowEvent</code>, it invokes the
     * <code>processWindowEvent</code> method, else it invokes its
     * superclass's <code>processEvent</code>.
     * <p>Note that if the event parameter is <code>null</code>
     * the behavior is unspecified and may result in an
     * exception.
     *
     * @param e the event
     */
    protected void processEvent(AWTEvent e) {
        if (e instanceof WindowEvent) {
            switch (e.getID()) {
                case WindowEvent.WINDOW_OPENED:
                case WindowEvent.WINDOW_CLOSING:
                case WindowEvent.WINDOW_CLOSED:
                case WindowEvent.WINDOW_ICONIFIED:
                case WindowEvent.WINDOW_DEICONIFIED:
                case WindowEvent.WINDOW_ACTIVATED:
                case WindowEvent.WINDOW_DEACTIVATED:
                    processWindowEvent((WindowEvent)e);
                    break;
                case WindowEvent.WINDOW_GAINED_FOCUS:
                case WindowEvent.WINDOW_LOST_FOCUS:
                    processWindowFocusEvent((WindowEvent)e);
                    break;
                case WindowEvent.WINDOW_STATE_CHANGED:
		    processWindowStateEvent((WindowEvent)e);
                default:
                    break;
            }
            return;
        }
	super.processEvent(e);
    }

    /** 
     * Processes window events occurring on this window by
     * dispatching them to any registered WindowListener objects.
     * NOTE: This method will not be called unless window events
     * are enabled for this component; this happens when one of the
     * following occurs:
     * <ul>
     * <li>A WindowListener object is registered via
     *     <code>addWindowListener</code>
     * <li>Window events are enabled via <code>enableEvents</code>
     * </ul>
     * <p>Note that if the event parameter is <code>null</code>
     * the behavior is unspecified and may result in an
     * exception.
     *
     * @param e the window event
     * @see Component#enableEvents
     */  
    protected void processWindowEvent(WindowEvent e) {
        WindowListener listener = windowListener;
        if (listener != null) {
            switch(e.getID()) {
                case WindowEvent.WINDOW_OPENED:
                    listener.windowOpened(e);
                    break;
                case WindowEvent.WINDOW_CLOSING:
                    listener.windowClosing(e);
                    break;
                case WindowEvent.WINDOW_CLOSED:
                    listener.windowClosed(e);
                    break;
                case WindowEvent.WINDOW_ICONIFIED:
                    listener.windowIconified(e);
                    break;
                case WindowEvent.WINDOW_DEICONIFIED:
                    listener.windowDeiconified(e);
                    break;
                case WindowEvent.WINDOW_ACTIVATED:
                    listener.windowActivated(e);
                    break;
                case WindowEvent.WINDOW_DEACTIVATED:
                    listener.windowDeactivated(e);
                    break;
                default:
                    break;
            }
        }
    }

    /**
     * Processes window focus event occuring on this window by
     * dispatching them to any registered WindowFocusListener objects.
     * NOTE: this method will not be called unless window focus events
     * are enabled for this window. This happens when one of the
     * following occurs:
     * <ul>
     * <li>a WindowFocusListener is registered via
     *     <code>addWindowFocusListener</code>
     * <li>Window focus events are enabled via <code>enableEvents</code>
     * </ul>
     * <p>Note that if the event parameter is <code>null</code>
     * the behavior is unspecified and may result in an
     * exception.
     *
     * @param e the window focus event
     * @see Component#enableEvents
     */
    protected void processWindowFocusEvent(WindowEvent e) {
        WindowFocusListener listener = windowFocusListener;
        if (listener != null) {
            switch (e.getID()) {
                case WindowEvent.WINDOW_GAINED_FOCUS:
                    listener.windowGainedFocus(e);
                    break;
                case WindowEvent.WINDOW_LOST_FOCUS:
                    listener.windowLostFocus(e);
                    break;
                default:
                    break;
            }
        }
    }

    /**
     * Processes window state event occuring on this window by
     * dispatching them to any registered <code>WindowStateListener</code>
     * objects.
     * NOTE: this method will not be called unless window state events
     * are enabled for this window.  This happens when one of the
     * following occurs:
     * <ul>
     * <li>a <code>WindowStateListener</code> is registered via
     *    <code>addWindowStateListener</code>
     * <li>window state events are enabled via <code>enableEvents</code>
     * </ul>
     * <p>Note that if the event parameter is <code>null</code>
     * the behavior is unspecified and may result in an
     * exception.
     *
     * @param e the window state event
     * @see java.awt.Component#enableEvents
     * @since 1.4
     */
    protected void processWindowStateEvent(WindowEvent e) {
        WindowStateListener listener = windowStateListener;
	if (listener != null) {
	    switch (e.getID()) {
		case WindowEvent.WINDOW_STATE_CHANGED:
		    listener.windowStateChanged(e);
		    break;
		default:
		    break;
	    }
	}
    }

    /**
     * Implements a debugging hook -- checks to see if
     * the user has typed <i>control-shift-F1</i>.  If so,
     * the list of child windows is dumped to <code>System.out</code>.
     * @param e  the keyboard event
     */
    void preProcessKeyEvent(KeyEvent e) {
        // Dump the list of child windows to System.out.
        if (e.isActionKey() && e.getKeyCode() == KeyEvent.VK_F1 &&
            e.isControlDown() && e.isShiftDown() && 
            e.getID() == KeyEvent.KEY_PRESSED) {
            list(System.out, 0);
        }
    }

    void postProcessKeyEvent(KeyEvent e) {
	// Do nothing
    }
  
    /**
     * Returns the child Component of this Window that has focus if this Window
     * is focused; returns null otherwise.
     *
     * @return the child Component with focus, or null if this Window is not
     *         focused
     * @see #getMostRecentFocusOwner
     * @see #isFocused
     */
    public Component getFocusOwner() {
	return (isFocused())
	    ? KeyboardFocusManager.getCurrentKeyboardFocusManager().
	          getFocusOwner()
	    : null;
    }
 
    /**
     * Returns the child Component of this Window that will receive the focus
     * when this Window is focused. If this Window is currently focused, this
     * method returns the same Component as <code>getFocusOwner()</code>. If
     * this Window is not focused, then the child Component that most recently 
     * requested focus will be returned. If no child Component has ever
     * requested focus, and this is a focusable Window, then this Window's
     * initial focusable Component is returned. If no child Component has ever
     * requested focus, and this is a non-focusable Window, null is returned.
     *
     * @return the child Component that will receive focus when this Window is
     *         focused
     * @see #getFocusOwner
     * @see #isFocused
     * @see #isFocusableWindow
     * @since 1.4
     */
    public Component getMostRecentFocusOwner() {
	if (isFocused()) {
	    return getFocusOwner();
	} else {
	    Component mostRecent =
		KeyboardFocusManager.getMostRecentFocusOwner(this);
	    if (mostRecent != null) {
		return mostRecent;
	    } else {
		return (isFocusableWindow())
		    ? getFocusTraversalPolicy().getInitialComponent(this)
		    : null;
	    }
        }
    }