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	/*
	* Copyright (c) 1996, 2013, 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 java.awt;

	import java.awt.event.*;
	import java.lang.reflect.Array;
	import java.util.EventListener;
	import java.io.Serializable;
	import java.io.ObjectOutputStream;
	import java.io.IOException;
	import java.util.EventListener;


	/**
	* {@code AWTEventMulticaster} implements efficient and thread-safe multi-cast
	* event dispatching for the AWT events defined in the {@code java.awt.event}
	* package.
	* <p>
	* The following example illustrates how to use this class:
	*
	* <pre><code>
	* public myComponent extends Component {
	* ActionListener actionListener = null;
	*
	* public synchronized void addActionListener(ActionListener l) {
	* actionListener = AWTEventMulticaster.add(actionListener, l);
	* }
	* public synchronized void removeActionListener(ActionListener l) {
	* actionListener = AWTEventMulticaster.remove(actionListener, l);
	* }
	* public void processEvent(AWTEvent e) {
	* // when event occurs which causes "action" semantic
	* ActionListener listener = actionListener;
	* if (listener != null) {
	* listener.actionPerformed(new ActionEvent());
	* }
	* }
	* }
	* </code></pre>
	* The important point to note is the first argument to the {@code
	* add} and {@code remove} methods is the field maintaining the
	* listeners. In addition you must assign the result of the {@code add}
	* and {@code remove} methods to the field maintaining the listeners.
	* <p>
	* {@code AWTEventMulticaster} is implemented as a pair of {@code
	* EventListeners} that are set at construction time. {@code
	* AWTEventMulticaster} is immutable. The {@code add} and {@code
	* remove} methods do not alter {@code AWTEventMulticaster} in
	* anyway. If necessary, a new {@code AWTEventMulticaster} is
	* created. In this way it is safe to add and remove listeners during
	* the process of an event dispatching. However, event listeners
	* added during the process of an event dispatch operation are not
	* notified of the event currently being dispatched.
	* <p>
	* All of the {@code add} methods allow {@code null} arguments. If the
	* first argument is {@code null}, the second argument is returned. If
	* the first argument is not {@code null} and the second argument is
	* {@code null}, the first argument is returned. If both arguments are
	* {@code non-null}, a new {@code AWTEventMulticaster} is created using
	* the two arguments and returned.
	* <p>
	* For the {@code remove} methods that take two arguments, the following is
	* returned:
	* <ul>
	* <li>{@code null}, if the first argument is {@code null}, or
	* the arguments are equal, by way of {@code ==}.
	* <li>the first argument, if the first argument is not an instance of
	* {@code AWTEventMulticaster}.
	* <li>result of invoking {@code remove(EventListener)} on the
	* first argument, supplying the second argument to the
	* {@code remove(EventListener)} method.
	* </ul>
	* <p>Swing makes use of
	* {@link javax.swing.event.EventListenerList EventListenerList} for
	* similar logic. Refer to it for details.
	*
	* @see javax.swing.event.EventListenerList
	*
	* @author John Rose
	* @author Amy Fowler
	* @since 1.1
	*/

	public class AWTEventMulticaster implements
	ComponentListener, ContainerListener, FocusListener, KeyListener,
	MouseListener, MouseMotionListener, WindowListener, WindowFocusListener,
	WindowStateListener, ActionListener, ItemListener, AdjustmentListener,
	TextListener, InputMethodListener, HierarchyListener,
	HierarchyBoundsListener, MouseWheelListener {

	protected final EventListener a, b;

	/**
	* Creates an event multicaster instance which chains listener-a
	* with listener-b. Input parameters <code>a</code> and <code>b</code>
	* should not be <code>null</code>, though implementations may vary in
	* choosing whether or not to throw <code>NullPointerException</code>
	* in that case.
	* @param a listener-a
	* @param b listener-b
	*/
	protected AWTEventMulticaster(EventListener a, EventListener b) {
	this.a = a; this.b = b;
	}

	/**
	* Removes a listener from this multicaster.
	* <p>
	* The returned multicaster contains all the listeners in this
	* multicaster with the exception of all occurrences of {@code oldl}.
	* If the resulting multicaster contains only one regular listener
	* the regular listener may be returned. If the resulting multicaster
	* is empty, then {@code null} may be returned instead.
	* <p>
	* No exception is thrown if {@code oldl} is {@code null}.
	*
	* @param oldl the listener to be removed
	* @return resulting listener
	*/
	protected EventListener remove(EventListener oldl) {
	if (oldl == a) return b;
	if (oldl == b) return a;
	EventListener a2 = removeInternal(a, oldl);
	EventListener b2 = removeInternal(b, oldl);
	if (a2 == a && b2 == b) {
	return this; // it's not here
	}
	return addInternal(a2, b2);
	}

	/**
	* Handles the componentResized event by invoking the
	* componentResized methods on listener-a and listener-b.
	* @param e the component event
	*/
	public void componentResized(ComponentEvent e) {
	((ComponentListener)a).componentResized(e);
	((ComponentListener)b).componentResized(e);
	}

	/**
	* Handles the componentMoved event by invoking the
	* componentMoved methods on listener-a and listener-b.
	* @param e the component event
	*/
	public void componentMoved(ComponentEvent e) {
	((ComponentListener)a).componentMoved(e);
	((ComponentListener)b).componentMoved(e);
	}

	/**
	* Handles the componentShown event by invoking the
	* componentShown methods on listener-a and listener-b.
	* @param e the component event
	*/
	public void componentShown(ComponentEvent e) {
	((ComponentListener)a).componentShown(e);
	((ComponentListener)b).componentShown(e);
	}

	/**
	* Handles the componentHidden event by invoking the
	* componentHidden methods on listener-a and listener-b.
	* @param e the component event
	*/
	public void componentHidden(ComponentEvent e) {
	((ComponentListener)a).componentHidden(e);
	((ComponentListener)b).componentHidden(e);
	}

	/**
	* Handles the componentAdded container event by invoking the
	* componentAdded methods on listener-a and listener-b.
	* @param e the component event
	*/
	public void componentAdded(ContainerEvent e) {
	((ContainerListener)a).componentAdded(e);
	((ContainerListener)b).componentAdded(e);
	}

	/**
	* Handles the componentRemoved container event by invoking the
	* componentRemoved methods on listener-a and listener-b.
	* @param e the component event
	*/
	public void componentRemoved(ContainerEvent e) {
	((ContainerListener)a).componentRemoved(e);
	((ContainerListener)b).componentRemoved(e);
	}

	/**
	* Handles the focusGained event by invoking the
	* focusGained methods on listener-a and listener-b.
	* @param e the focus event
	*/
	public void focusGained(FocusEvent e) {
	((FocusListener)a).focusGained(e);
	((FocusListener)b).focusGained(e);
	}

	/**
	* Handles the focusLost event by invoking the
	* focusLost methods on listener-a and listener-b.
	* @param e the focus event
	*/
	public void focusLost(FocusEvent e) {
	((FocusListener)a).focusLost(e);
	((FocusListener)b).focusLost(e);
	}

	/**
	* Handles the keyTyped event by invoking the
	* keyTyped methods on listener-a and listener-b.
	* @param e the key event
	*/
	public void keyTyped(KeyEvent e) {
	((KeyListener)a).keyTyped(e);
	((KeyListener)b).keyTyped(e);
	}

	/**
	* Handles the keyPressed event by invoking the
	* keyPressed methods on listener-a and listener-b.
	* @param e the key event
	*/
	public void keyPressed(KeyEvent e) {
	((KeyListener)a).keyPressed(e);
	((KeyListener)b).keyPressed(e);
	}

	/**
	* Handles the keyReleased event by invoking the
	* keyReleased methods on listener-a and listener-b.
	* @param e the key event
	*/
	public void keyReleased(KeyEvent e) {
	((KeyListener)a).keyReleased(e);
	((KeyListener)b).keyReleased(e);
	}

	/**
	* Handles the mouseClicked event by invoking the
	* mouseClicked methods on listener-a and listener-b.
	* @param e the mouse event
	*/
	public void mouseClicked(MouseEvent e) {
	((MouseListener)a).mouseClicked(e);
	((MouseListener)b).mouseClicked(e);
	}

	/**
	* Handles the mousePressed event by invoking the
	* mousePressed methods on listener-a and listener-b.
	* @param e the mouse event
	*/
	public void mousePressed(MouseEvent e) {
	((MouseListener)a).mousePressed(e);
	((MouseListener)b).mousePressed(e);
	}

	/**
	* Handles the mouseReleased event by invoking the
	* mouseReleased methods on listener-a and listener-b.
	* @param e the mouse event
	*/
	public void mouseReleased(MouseEvent e) {
	((MouseListener)a).mouseReleased(e);
	((MouseListener)b).mouseReleased(e);
	}

	/**
	* Handles the mouseEntered event by invoking the
	* mouseEntered methods on listener-a and listener-b.
	* @param e the mouse event
	*/
	public void mouseEntered(MouseEvent e) {
	((MouseListener)a).mouseEntered(e);
	((MouseListener)b).mouseEntered(e);
	}

	/**
	* Handles the mouseExited event by invoking the
	* mouseExited methods on listener-a and listener-b.
	* @param e the mouse event
	*/
	public void mouseExited(MouseEvent e) {
	((MouseListener)a).mouseExited(e);
	((MouseListener)b).mouseExited(e);
	}

	/**
	* Handles the mouseDragged event by invoking the
	* mouseDragged methods on listener-a and listener-b.
	* @param e the mouse event
	*/
	public void mouseDragged(MouseEvent e) {
	((MouseMotionListener)a).mouseDragged(e);
	((MouseMotionListener)b).mouseDragged(e);
	}

	/**
	* Handles the mouseMoved event by invoking the
	* mouseMoved methods on listener-a and listener-b.
	* @param e the mouse event
	*/
	public void mouseMoved(MouseEvent e) {
	((MouseMotionListener)a).mouseMoved(e);
	((MouseMotionListener)b).mouseMoved(e);
	}

	/**
	* Handles the windowOpened event by invoking the
	* windowOpened methods on listener-a and listener-b.
	* @param e the window event
	*/
	public void windowOpened(WindowEvent e) {
	((WindowListener)a).windowOpened(e);
	((WindowListener)b).windowOpened(e);
	}

	/**
	* Handles the windowClosing event by invoking the
	* windowClosing methods on listener-a and listener-b.
	* @param e the window event
	*/
	public void windowClosing(WindowEvent e) {
	((WindowListener)a).windowClosing(e);
	((WindowListener)b).windowClosing(e);
	}

	/**
	* Handles the windowClosed event by invoking the
	* windowClosed methods on listener-a and listener-b.
	* @param e the window event
	*/
	public void windowClosed(WindowEvent e) {
	((WindowListener)a).windowClosed(e);
	((WindowListener)b).windowClosed(e);
	}

	/**
	* Handles the windowIconified event by invoking the
	* windowIconified methods on listener-a and listener-b.
	* @param e the window event
	*/
	public void windowIconified(WindowEvent e) {
	((WindowListener)a).windowIconified(e);
	((WindowListener)b).windowIconified(e);
	}

	/**
	* Handles the windowDeiconfied event by invoking the
	* windowDeiconified methods on listener-a and listener-b.
	* @param e the window event
	*/
	public void windowDeiconified(WindowEvent e) {
	((WindowListener)a).windowDeiconified(e);
	((WindowListener)b).windowDeiconified(e);
	}

	/**
	* Handles the windowActivated event by invoking the
	* windowActivated methods on listener-a and listener-b.
	* @param e the window event
	*/
	public void windowActivated(WindowEvent e) {
	((WindowListener)a).windowActivated(e);
	((WindowListener)b).windowActivated(e);
	}

	/**
	* Handles the windowDeactivated event by invoking the
	* windowDeactivated methods on listener-a and listener-b.
	* @param e the window event
	*/
	public void windowDeactivated(WindowEvent e) {
	((WindowListener)a).windowDeactivated(e);
	((WindowListener)b).windowDeactivated(e);
	}

	/**
	* Handles the windowStateChanged event by invoking the
	* windowStateChanged methods on listener-a and listener-b.
	* @param e the window event
	* @since 1.4
	*/
	public void windowStateChanged(WindowEvent e) {
	((WindowStateListener)a).windowStateChanged(e);
	((WindowStateListener)b).windowStateChanged(e);
	}


	/**
	* Handles the windowGainedFocus event by invoking the windowGainedFocus
	* methods on listener-a and listener-b.
	* @param e the window event
	* @since 1.4
	*/
	public void windowGainedFocus(WindowEvent e) {
	((WindowFocusListener)a).windowGainedFocus(e);
	((WindowFocusListener)b).windowGainedFocus(e);
	}

	/**
	* Handles the windowLostFocus event by invoking the windowLostFocus
	* methods on listener-a and listener-b.
	* @param e the window event
	* @since 1.4
	*/
	public void windowLostFocus(WindowEvent e) {
	((WindowFocusListener)a).windowLostFocus(e);
	((WindowFocusListener)b).windowLostFocus(e);
	}

	/**
	* Handles the actionPerformed event by invoking the
	* actionPerformed methods on listener-a and listener-b.
	* @param e the action event
	*/
	public void actionPerformed(ActionEvent e) {
	((ActionListener)a).actionPerformed(e);
	((ActionListener)b).actionPerformed(e);
	}

	/**
	* Handles the itemStateChanged event by invoking the
	* itemStateChanged methods on listener-a and listener-b.
	* @param e the item event
	*/
	public void itemStateChanged(ItemEvent e) {
	((ItemListener)a).itemStateChanged(e);
	((ItemListener)b).itemStateChanged(e);
	}

	/**
	* Handles the adjustmentValueChanged event by invoking the
	* adjustmentValueChanged methods on listener-a and listener-b.
	* @param e the adjustment event
	*/
	public void adjustmentValueChanged(AdjustmentEvent e) {
	((AdjustmentListener)a).adjustmentValueChanged(e);
	((AdjustmentListener)b).adjustmentValueChanged(e);
	}
	public void textValueChanged(TextEvent e) {
	((TextListener)a).textValueChanged(e);
	((TextListener)b).textValueChanged(e);
	}

	/**
	* Handles the inputMethodTextChanged event by invoking the
	* inputMethodTextChanged methods on listener-a and listener-b.
	* @param e the item event
	*/
	public void inputMethodTextChanged(InputMethodEvent e) {
	((InputMethodListener)a).inputMethodTextChanged(e);
	((InputMethodListener)b).inputMethodTextChanged(e);
	}

	/**
	* Handles the caretPositionChanged event by invoking the
	* caretPositionChanged methods on listener-a and listener-b.
	* @param e the item event
	*/
	public void caretPositionChanged(InputMethodEvent e) {
	((InputMethodListener)a).caretPositionChanged(e);
	((InputMethodListener)b).caretPositionChanged(e);
	}

	/**
	* Handles the hierarchyChanged event by invoking the
	* hierarchyChanged methods on listener-a and listener-b.
	* @param e the item event
	* @since 1.3
	*/
	public void hierarchyChanged(HierarchyEvent e) {
	((HierarchyListener)a).hierarchyChanged(e);
	((HierarchyListener)b).hierarchyChanged(e);
	}

	/**
	* Handles the ancestorMoved event by invoking the
	* ancestorMoved methods on listener-a and listener-b.
	* @param e the item event
	* @since 1.3
	*/
	public void ancestorMoved(HierarchyEvent e) {
	((HierarchyBoundsListener)a).ancestorMoved(e);
	((HierarchyBoundsListener)b).ancestorMoved(e);
	}

	/**
	* Handles the ancestorResized event by invoking the
	* ancestorResized methods on listener-a and listener-b.
	* @param e the item event
	* @since 1.3
	*/
	public void ancestorResized(HierarchyEvent e) {
	((HierarchyBoundsListener)a).ancestorResized(e);
	((HierarchyBoundsListener)b).ancestorResized(e);
	}

	/**
	* Handles the mouseWheelMoved event by invoking the
	* mouseWheelMoved methods on listener-a and listener-b.
	* @param e the mouse event
	* @since 1.4
	*/
	public void mouseWheelMoved(MouseWheelEvent e) {
	((MouseWheelListener)a).mouseWheelMoved(e);
	((MouseWheelListener)b).mouseWheelMoved(e);
	}

	/**
	* Adds component-listener-a with component-listener-b and
	* returns the resulting multicast listener.
	* @param a component-listener-a
	* @param b component-listener-b
	*/
	public static ComponentListener add(ComponentListener a, ComponentListener b) {
	return (ComponentListener)addInternal(a, b);
	}

	/**
	* Adds container-listener-a with container-listener-b and
	* returns the resulting multicast listener.
	* @param a container-listener-a
	* @param b container-listener-b
	*/
	public static ContainerListener add(ContainerListener a, ContainerListener b) {
	return (ContainerListener)addInternal(a, b);
	}

	/**
	* Adds focus-listener-a with focus-listener-b and
	* returns the resulting multicast listener.
	* @param a focus-listener-a
	* @param b focus-listener-b
	*/
	public static FocusListener add(FocusListener a, FocusListener b) {
	return (FocusListener)addInternal(a, b);
	}

	/**
	* Adds key-listener-a with key-listener-b and
	* returns the resulting multicast listener.
	* @param a key-listener-a
	* @param b key-listener-b
	*/
	public static KeyListener add(KeyListener a, KeyListener b) {
	return (KeyListener)addInternal(a, b);
	}

	/**
	* Adds mouse-listener-a with mouse-listener-b and
	* returns the resulting multicast listener.
	* @param a mouse-listener-a
	* @param b mouse-listener-b
	*/
	public static MouseListener add(MouseListener a, MouseListener b) {
	return (MouseListener)addInternal(a, b);
	}

	/**
	* Adds mouse-motion-listener-a with mouse-motion-listener-b and
	* returns the resulting multicast listener.
	* @param a mouse-motion-listener-a
	* @param b mouse-motion-listener-b
	*/
	public static MouseMotionListener add(MouseMotionListener a, MouseMotionListener b) {
	return (MouseMotionListener)addInternal(a, b);
	}

	/**
	* Adds window-listener-a with window-listener-b and
	* returns the resulting multicast listener.
	* @param a window-listener-a
	* @param b window-listener-b
	*/
	public static WindowListener add(WindowListener a, WindowListener b) {
	return (WindowListener)addInternal(a, b);
	}

	/**
	* Adds window-state-listener-a with window-state-listener-b
	* and returns the resulting multicast listener.
	* @param a window-state-listener-a
	* @param b window-state-listener-b
	* @since 1.4
	*/
	public static WindowStateListener add(WindowStateListener a,
	WindowStateListener b) {
	return (WindowStateListener)addInternal(a, b);
	}

	/**
	* Adds window-focus-listener-a with window-focus-listener-b
	* and returns the resulting multicast listener.
	* @param a window-focus-listener-a
	* @param b window-focus-listener-b
	* @since 1.4
	*/
	public static WindowFocusListener add(WindowFocusListener a,
	WindowFocusListener b) {
	return (WindowFocusListener)addInternal(a, b);
	}

	/**
	* Adds action-listener-a with action-listener-b and
	* returns the resulting multicast listener.
	* @param a action-listener-a
	* @param b action-listener-b
	*/
	public static ActionListener add(ActionListener a, ActionListener b) {
	return (ActionListener)addInternal(a, b);
	}

	/**
	* Adds item-listener-a with item-listener-b and
	* returns the resulting multicast listener.
	* @param a item-listener-a
	* @param b item-listener-b
	*/
	public static ItemListener add(ItemListener a, ItemListener b) {
	return (ItemListener)addInternal(a, b);
	}

	/**
	* Adds adjustment-listener-a with adjustment-listener-b and
	* returns the resulting multicast listener.
	* @param a adjustment-listener-a
	* @param b adjustment-listener-b
	*/
	public static AdjustmentListener add(AdjustmentListener a, AdjustmentListener b) {
	return (AdjustmentListener)addInternal(a, b);
	}
	public static TextListener add(TextListener a, TextListener b) {
	return (TextListener)addInternal(a, b);
	}

	/**
	* Adds input-method-listener-a with input-method-listener-b and
	* returns the resulting multicast listener.
	* @param a input-method-listener-a
	* @param b input-method-listener-b
	*/
	public static InputMethodListener add(InputMethodListener a, InputMethodListener b) {
	return (InputMethodListener)addInternal(a, b);
	}

	/**
	* Adds hierarchy-listener-a with hierarchy-listener-b and
	* returns the resulting multicast listener.
	* @param a hierarchy-listener-a
	* @param b hierarchy-listener-b
	* @since 1.3
	*/
	public static HierarchyListener add(HierarchyListener a, HierarchyListener b) {
	return (HierarchyListener)addInternal(a, b);
	}

	/**
	* Adds hierarchy-bounds-listener-a with hierarchy-bounds-listener-b and
	* returns the resulting multicast listener.
	* @param a hierarchy-bounds-listener-a
	* @param b hierarchy-bounds-listener-b
	* @since 1.3
	*/
	public static HierarchyBoundsListener add(HierarchyBoundsListener a, HierarchyBoundsListener b) {
	return (HierarchyBoundsListener)addInternal(a, b);
	}

	/**
	* Adds mouse-wheel-listener-a with mouse-wheel-listener-b and
	* returns the resulting multicast listener.
	* @param a mouse-wheel-listener-a
	* @param b mouse-wheel-listener-b
	* @since 1.4
	*/
	public static MouseWheelListener add(MouseWheelListener a,
	MouseWheelListener b) {
	return (MouseWheelListener)addInternal(a, b);
	}

	/**
	* Removes the old component-listener from component-listener-l and
	* returns the resulting multicast listener.
	* @param l component-listener-l
	* @param oldl the component-listener being removed
	*/
	public static ComponentListener remove(ComponentListener l, ComponentListener oldl) {
	return (ComponentListener) removeInternal(l, oldl);
	}

	/**
	* Removes the old container-listener from container-listener-l and
	* returns the resulting multicast listener.
	* @param l container-listener-l
	* @param oldl the container-listener being removed
	*/
	public static ContainerListener remove(ContainerListener l, ContainerListener oldl) {
	return (ContainerListener) removeInternal(l, oldl);
	}

	/**
	* Removes the old focus-listener from focus-listener-l and
	* returns the resulting multicast listener.
	* @param l focus-listener-l
	* @param oldl the focus-listener being removed
	*/
	public static FocusListener remove(FocusListener l, FocusListener oldl) {
	return (FocusListener) removeInternal(l, oldl);
	}

	/**
	* Removes the old key-listener from key-listener-l and
	* returns the resulting multicast listener.
	* @param l key-listener-l
	* @param oldl the key-listener being removed
	*/
	public static KeyListener remove(KeyListener l, KeyListener oldl) {
	return (KeyListener) removeInternal(l, oldl);
	}

	/**
	* Removes the old mouse-listener from mouse-listener-l and
	* returns the resulting multicast listener.
	* @param l mouse-listener-l
	* @param oldl the mouse-listener being removed
	*/
	public static MouseListener remove(MouseListener l, MouseListener oldl) {
	return (MouseListener) removeInternal(l, oldl);
	}

	/**
	* Removes the old mouse-motion-listener from mouse-motion-listener-l
	* and returns the resulting multicast listener.
	* @param l mouse-motion-listener-l
	* @param oldl the mouse-motion-listener being removed
	*/
	public static MouseMotionListener remove(MouseMotionListener l, MouseMotionListener oldl) {
	return (MouseMotionListener) removeInternal(l, oldl);
	}

	/**
	* Removes the old window-listener from window-listener-l and
	* returns the resulting multicast listener.
	* @param l window-listener-l
	* @param oldl the window-listener being removed
	*/
	public static WindowListener remove(WindowListener l, WindowListener oldl) {
	return (WindowListener) removeInternal(l, oldl);
	}

	/**
	* Removes the old window-state-listener from window-state-listener-l
	* and returns the resulting multicast listener.
	* @param l window-state-listener-l
	* @param oldl the window-state-listener being removed
	* @since 1.4
	*/
	public static WindowStateListener remove(WindowStateListener l,
	WindowStateListener oldl) {
	return (WindowStateListener) removeInternal(l, oldl);
	}

	/**
	* Removes the old window-focus-listener from window-focus-listener-l
	* and returns the resulting multicast listener.
	* @param l window-focus-listener-l
	* @param oldl the window-focus-listener being removed
	* @since 1.4
	*/
	public static WindowFocusListener remove(WindowFocusListener l,
	WindowFocusListener oldl) {
	return (WindowFocusListener) removeInternal(l, oldl);
	}

	/**
	* Removes the old action-listener from action-listener-l and
	* returns the resulting multicast listener.
	* @param l action-listener-l
	* @param oldl the action-listener being removed
	*/
	public static ActionListener remove(ActionListener l, ActionListener oldl) {
	return (ActionListener) removeInternal(l, oldl);
	}

	/**
	* Removes the old item-listener from item-listener-l and
	* returns the resulting multicast listener.
	* @param l item-listener-l
	* @param oldl the item-listener being removed
	*/
	public static ItemListener remove(ItemListener l, ItemListener oldl) {
	return (ItemListener) removeInternal(l, oldl);
	}

	/**
	* Removes the old adjustment-listener from adjustment-listener-l and
	* returns the resulting multicast listener.
	* @param l adjustment-listener-l
	* @param oldl the adjustment-listener being removed
	*/
	public static AdjustmentListener remove(AdjustmentListener l, AdjustmentListener oldl) {
	return (AdjustmentListener) removeInternal(l, oldl);
	}
	public static TextListener remove(TextListener l, TextListener oldl) {
	return (TextListener) removeInternal(l, oldl);
	}

	/**
	* Removes the old input-method-listener from input-method-listener-l and
	* returns the resulting multicast listener.
	* @param l input-method-listener-l
	* @param oldl the input-method-listener being removed
	*/
	public static InputMethodListener remove(InputMethodListener l, InputMethodListener oldl) {
	return (InputMethodListener) removeInternal(l, oldl);
	}

	/**
	* Removes the old hierarchy-listener from hierarchy-listener-l and
	* returns the resulting multicast listener.
	* @param l hierarchy-listener-l
	* @param oldl the hierarchy-listener being removed
	* @since 1.3
	*/
	public static HierarchyListener remove(HierarchyListener l, HierarchyListener oldl) {
	return (HierarchyListener) removeInternal(l, oldl);
	}

	/**
	* Removes the old hierarchy-bounds-listener from
	* hierarchy-bounds-listener-l and returns the resulting multicast
	* listener.
	* @param l hierarchy-bounds-listener-l
	* @param oldl the hierarchy-bounds-listener being removed
	* @since 1.3
	*/
	public static HierarchyBoundsListener remove(HierarchyBoundsListener l, HierarchyBoundsListener oldl) {
	return (HierarchyBoundsListener) removeInternal(l, oldl);
	}

	/**
	* Removes the old mouse-wheel-listener from mouse-wheel-listener-l
	* and returns the resulting multicast listener.
	* @param l mouse-wheel-listener-l
	* @param oldl the mouse-wheel-listener being removed
	* @since 1.4
	*/
	public static MouseWheelListener remove(MouseWheelListener l,
	MouseWheelListener oldl) {
	return (MouseWheelListener) removeInternal(l, oldl);
	}

	/**
	* Returns the resulting multicast listener from adding listener-a
	* and listener-b together.
	* If listener-a is null, it returns listener-b;
	* If listener-b is null, it returns listener-a
	* If neither are null, then it creates and returns
	* a new AWTEventMulticaster instance which chains a with b.
	* @param a event listener-a
	* @param b event listener-b
	*/
	protected static EventListener addInternal(EventListener a, EventListener b) {
	if (a == null) return b;
	if (b == null) return a;
	return new AWTEventMulticaster(a, b);
	}

	/**
	* Returns the resulting multicast listener after removing the
	* old listener from listener-l.
	* If listener-l equals the old listener OR listener-l is null,
	* returns null.
	* Else if listener-l is an instance of AWTEventMulticaster,
	* then it removes the old listener from it.
	* Else, returns listener l.
	* @param l the listener being removed from
	* @param oldl the listener being removed
	*/
	protected static EventListener removeInternal(EventListener l, EventListener oldl) {
	if (l == oldl \|\| l == null) {
	return null;
	} else if (l instanceof AWTEventMulticaster) {
	return ((AWTEventMulticaster)l).remove(oldl);
	} else {
	return l; // it's not here
	}
	}


	/* Serialization support.
	*/

	protected void saveInternal(ObjectOutputStream s, String k) throws IOException {
	if (a instanceof AWTEventMulticaster) {
	((AWTEventMulticaster)a).saveInternal(s, k);
	}
	else if (a instanceof Serializable) {
	s.writeObject(k);
	s.writeObject(a);
	}

	if (b instanceof AWTEventMulticaster) {
	((AWTEventMulticaster)b).saveInternal(s, k);
	}
	else if (b instanceof Serializable) {
	s.writeObject(k);
	s.writeObject(b);
	}
	}

	protected static void save(ObjectOutputStream s, String k, EventListener l) throws IOException {
	if (l == null) {
	return;
	}
	else if (l instanceof AWTEventMulticaster) {
	((AWTEventMulticaster)l).saveInternal(s, k);
	}
	else if (l instanceof Serializable) {
	s.writeObject(k);
	s.writeObject(l);
	}
	}

	/*
	* Recursive method which returns a count of the number of listeners in
	* EventListener, handling the (common) case of l actually being an
	* AWTEventMulticaster. Additionally, only listeners of type listenerType
	* are counted. Method modified to fix bug 4513402. -bchristi
	*/
	private static int getListenerCount(EventListener l, Class<?> listenerType) {
	if (l instanceof AWTEventMulticaster) {
	AWTEventMulticaster mc = (AWTEventMulticaster)l;
	return getListenerCount(mc.a, listenerType) +
	getListenerCount(mc.b, listenerType);
	}
	else {
	// Only count listeners of correct type
	return listenerType.isInstance(l) ? 1 : 0;
	}
	}

	/*
	* Recusive method which populates EventListener array a with EventListeners
	* from l. l is usually an AWTEventMulticaster. Bug 4513402 revealed that
	* if l differed in type from the element type of a, an ArrayStoreException
	* would occur. Now l is only inserted into a if it's of the appropriate
	* type. -bchristi
	*/
	private static int populateListenerArray(EventListener[] a, EventListener l, int index) {
	if (l instanceof AWTEventMulticaster) {
	AWTEventMulticaster mc = (AWTEventMulticaster)l;
	int lhs = populateListenerArray(a, mc.a, index);
	return populateListenerArray(a, mc.b, lhs);
	}
	else if (a.getClass().getComponentType().isInstance(l)) {
	a[index] = l;
	return index + 1;
	}
	// Skip nulls, instances of wrong class
	else {
	return index;
	}
	}

	/**
	* Returns an array of all the objects chained as
	* <code><em>Foo</em>Listener</code>s by the specified
	* <code>java.util.EventListener</code>.
	* <code><em>Foo</em>Listener</code>s are chained by the
	* <code>AWTEventMulticaster</code> using the
	* <code>add<em>Foo</em>Listener</code> method.
	* If a <code>null</code> listener is specified, this method returns an
	* empty array. If the specified listener is not an instance of
	* <code>AWTEventMulticaster</code>, this method returns an array which
	* contains only the specified listener. If no such listeners are chained,
	* this method returns an empty array.
	*
	* @param l the specified <code>java.util.EventListener</code>
	* @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 chained as
	* <code><em>Foo</em>Listener</code>s by the specified multicast
	* listener, or an empty array if no such listeners have been
	* chained by the specified multicast listener
	* @exception NullPointerException if the specified
	* {@code listenertype} parameter is {@code null}
	* @exception ClassCastException if <code>listenerType</code>
	* doesn't specify a class or interface that implements
	* <code>java.util.EventListener</code>
	*
	* @since 1.4
	*/
	@SuppressWarnings("unchecked")
	public static <T extends EventListener> T[]
	getListeners(EventListener l, Class<T> listenerType)
	{
	if (listenerType == null) {
	throw new NullPointerException ("Listener type should not be null");
	}

	int n = getListenerCount(l, listenerType);
	T[] result = (T[])Array.newInstance(listenerType, n);
	populateListenerArray(result, l, 0);
	return result;
	}
	}

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