https://openjdk.java.net/ 
/*
 * Copyright (c) 2005, 2011, 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.awt.peer.TrayIconPeer;
import sun.awt.AppContext;
import sun.awt.SunToolkit;
import sun.awt.AWTAccessor;
import sun.awt.HeadlessToolkit;
import java.util.EventObject;
import java.security.AccessControlContext;
import java.security.AccessController;


A TrayIcon object represents a tray icon that can be added to the system tray. A TrayIcon can have a tooltip (text), an image, a popup
menu, and a set of listeners associated with it.

A TrayIcon can generate various 
MouseEvents and supports adding corresponding listeners to receive notification of these events. TrayIcon processes some
of the events by itself.  For example, by default, when the
right-mouse click is performed on the TrayIcon it
displays the specified popup menu.  When the mouse hovers
over the TrayIcon the tooltip is displayed.

Note: When the MouseEvent is
dispatched to its registered listeners its component
property will be set to null. (See ComponentEvent.getComponent) The source property will be set to this
TrayIcon. (See EventObject.getSource) 
Note: A well-behaved TrayIcon implementation will assign different gestures to showing a popup menu and selecting a tray icon. 
A TrayIcon can generate an 
ActionEvent. On some platforms, this occurs when the user selects the tray icon using either the mouse or keyboard. 
If a SecurityManager is installed, the AWTPermission accessSystemTray must be granted in order to create a TrayIcon. Otherwise the constructor will throw a SecurityException. 
 See the SystemTray class overview for an example on how to use the TrayIcon API.

Author:Bino George, Denis Mikhalkin, Sharon Zakhour, Anton Tarasov
See Also:
Since:1.6
/**
 * A <code>TrayIcon</code> object represents a tray icon that can be
 * added to the {@link SystemTray system tray}. A
 * <code>TrayIcon</code> can have a tooltip (text), an image, a popup
 * menu, and a set of listeners associated with it.
 *
 * <p>A <code>TrayIcon</code> can generate various {@link MouseEvent
 * MouseEvents} and supports adding corresponding listeners to receive
 * notification of these events.  <code>TrayIcon</code> processes some
 * of the events by itself.  For example, by default, when the
 * right-mouse click is performed on the <code>TrayIcon</code> it
 * displays the specified popup menu.  When the mouse hovers
 * over the <code>TrayIcon</code> the tooltip is displayed.
 *
 * <p><strong>Note:</strong> When the <code>MouseEvent</code> is
 * dispatched to its registered listeners its <code>component</code>
 * property will be set to <code>null</code>.  (See {@link
 * java.awt.event.ComponentEvent#getComponent}) The
 * <code>source</code> property will be set to this
 * <code>TrayIcon</code>. (See {@link
 * java.util.EventObject#getSource})
 *
 * <p><b>Note:</b> A well-behaved {@link TrayIcon} implementation
 * will assign different gestures to showing a popup menu and
 * selecting a tray icon.
 *
 * <p>A <code>TrayIcon</code> can generate an {@link ActionEvent
 * ActionEvent}.  On some platforms, this occurs when the user selects
 * the tray icon using either the mouse or keyboard.
 *
 * <p>If a SecurityManager is installed, the AWTPermission
 * {@code accessSystemTray} must be granted in order to create
 * a {@code TrayIcon}. Otherwise the constructor will throw a
 * SecurityException.
 *
 * <p> See the {@link SystemTray} class overview for an example on how
 * to use the <code>TrayIcon</code> API.
 *
 * @since 1.6
 * @see SystemTray#add
 * @see java.awt.event.ComponentEvent#getComponent
 * @see java.util.EventObject#getSource
 *
 * @author Bino George
 * @author Denis Mikhalkin
 * @author Sharon Zakhour
 * @author Anton Tarasov
 */
public class TrayIcon {

    private Image image;
    private String tooltip;
    private PopupMenu popup;
    private boolean autosize;
    private int id;
    private String actionCommand;

    transient private TrayIconPeer peer;

    transient MouseListener mouseListener;
    transient MouseMotionListener mouseMotionListener;
    transient ActionListener actionListener;

    /*
     * The tray icon's AccessControlContext.
     *
     * Unlike the acc in Component, this field is made final
     * because TrayIcon is not serializable.
     */
    private final AccessControlContext acc = AccessController.getContext();

    /*
     * Returns the acc this tray icon was constructed with.
     */
    final AccessControlContext getAccessControlContext() {
        if (acc == null) {
            throw new SecurityException("TrayIcon is missing AccessControlContext");
        }
        return acc;
    }

    static {
        Toolkit.loadLibraries();
        if (!GraphicsEnvironment.isHeadless()) {
            initIDs();
        }

        AWTAccessor.setTrayIconAccessor(
            new AWTAccessor.TrayIconAccessor() {
                public void addNotify(TrayIcon trayIcon) throws AWTException {
                    trayIcon.addNotify();
                }
                public void removeNotify(TrayIcon trayIcon) {
                    trayIcon.removeNotify();
                }
            });
    }

    private TrayIcon()
      throws UnsupportedOperationException, HeadlessException, SecurityException
    {
        SystemTray.checkSystemTrayAllowed();
        if (GraphicsEnvironment.isHeadless()) {
            throw new HeadlessException();
        }
        if (!SystemTray.isSupported()) {
            throw new UnsupportedOperationException();
        }
        SunToolkit.insertTargetMapping(this, AppContext.getAppContext());
    }

    
Creates a TrayIcon with the specified image.

Params:
  • image – the Image to be used
Throws:
See Also:
/**
     * Creates a <code>TrayIcon</code> with the specified image.
     *
     * @param image the <code>Image</code> to be used
     * @throws IllegalArgumentException if <code>image</code> is
     * <code>null</code>
     * @throws UnsupportedOperationException if the system tray isn't
     * supported by the current platform
     * @throws HeadlessException if
     * {@code GraphicsEnvironment.isHeadless()} returns {@code true}
     * @throws SecurityException if {@code accessSystemTray} permission
     * is not granted
     * @see SystemTray#add(TrayIcon)
     * @see TrayIcon#TrayIcon(Image, String, PopupMenu)
     * @see TrayIcon#TrayIcon(Image, String)
     * @see SecurityManager#checkPermission
     * @see AWTPermission
     */
    public TrayIcon(Image image) {
        this();
        if (image == null) {
            throw new IllegalArgumentException("creating TrayIcon with null Image");
        }
        setImage(image);
    }

    
Creates a TrayIcon with the specified image and
tooltip text.

Params:
  • image – the Image to be used
  • tooltip – the string to be used as tooltip text; if the
value is null no tooltip is shown
Throws:
See Also:
/**
     * Creates a <code>TrayIcon</code> with the specified image and
     * tooltip text.
     *
     * @param image the <code>Image</code> to be used
     * @param tooltip the string to be used as tooltip text; if the
     * value is <code>null</code> no tooltip is shown
     * @throws IllegalArgumentException if <code>image</code> is
     * <code>null</code>
     * @throws UnsupportedOperationException if the system tray isn't
     * supported by the current platform
     * @throws HeadlessException if
     * {@code GraphicsEnvironment.isHeadless()} returns {@code true}
     * @throws SecurityException if {@code accessSystemTray} permission
     * is not granted
     * @see SystemTray#add(TrayIcon)
     * @see TrayIcon#TrayIcon(Image)
     * @see TrayIcon#TrayIcon(Image, String, PopupMenu)
     * @see SecurityManager#checkPermission
     * @see AWTPermission
     */
    public TrayIcon(Image image, String tooltip) {
        this(image);
        setToolTip(tooltip);
    }

    
Creates a TrayIcon with the specified image,
tooltip and popup menu.

Params:
  • image – the Image to be used
  • tooltip – the string to be used as tooltip text; if the
value is null no tooltip is shown
  • popup – the menu to be used for the tray icon's popup
menu; if the value is null no popup menu is shown
Throws:
See Also:
/**
     * Creates a <code>TrayIcon</code> with the specified image,
     * tooltip and popup menu.
     *
     * @param image the <code>Image</code> to be used
     * @param tooltip the string to be used as tooltip text; if the
     * value is <code>null</code> no tooltip is shown
     * @param popup the menu to be used for the tray icon's popup
     * menu; if the value is <code>null</code> no popup menu is shown
     * @throws IllegalArgumentException if <code>image</code> is <code>null</code>
     * @throws UnsupportedOperationException if the system tray isn't
     * supported by the current platform
     * @throws HeadlessException if
     * {@code GraphicsEnvironment.isHeadless()} returns {@code true}
     * @throws SecurityException if {@code accessSystemTray} permission
     * is not granted
     * @see SystemTray#add(TrayIcon)
     * @see TrayIcon#TrayIcon(Image, String)
     * @see TrayIcon#TrayIcon(Image)
     * @see PopupMenu
     * @see MouseListener
     * @see #addMouseListener(MouseListener)
     * @see SecurityManager#checkPermission
     * @see AWTPermission
     */
    public TrayIcon(Image image, String tooltip, PopupMenu popup) {
        this(image, tooltip);
        setPopupMenu(popup);
    }

    
Sets the image for this TrayIcon. The previous tray icon image is discarded without calling the Image.flush method — you will need to call it manually. 
 If the image represents an animated image, it will be
animated automatically.

 See the setImageAutoSize(boolean) property for details on the size of the displayed image. 
 Calling this method with the same image that is currently
being used has no effect.

Params:
  • image – the non-null Image to be used
Throws:
See Also:
/**
     * Sets the image for this <code>TrayIcon</code>.  The previous
     * tray icon image is discarded without calling the {@link
     * java.awt.Image#flush} method &#151; you will need to call it
     * manually.
     *
     * <p> If the image represents an animated image, it will be
     * animated automatically.
     *
     * <p> See the {@link #setImageAutoSize(boolean)} property for
     * details on the size of the displayed image.
     *
     * <p> Calling this method with the same image that is currently
     * being used has no effect.
     *
     * @throws NullPointerException if <code>image</code> is <code>null</code>
     * @param image the non-null <code>Image</code> to be used
     * @see #getImage
     * @see Image
     * @see SystemTray#add(TrayIcon)
     * @see TrayIcon#TrayIcon(Image, String)
     */
    public void setImage(Image image) {
        if (image == null) {
            throw new NullPointerException("setting null Image");
        }
        this.image = image;

        TrayIconPeer peer = this.peer;
        if (peer != null) {
            peer.updateImage();
        }
    }

    
Returns the current image used for this TrayIcon.

See Also:
Returns:the image
/**
     * Returns the current image used for this <code>TrayIcon</code>.
     *
     * @return the image
     * @see #setImage(Image)
     * @see Image
     */
    public Image getImage() {
        return image;
    }

    
Sets the popup menu for this TrayIcon.  If
popup is null, no popup menu will be
associated with this TrayIcon.

Note that this popup must not be added to any
parent before or after it is set on the tray icon.  If you add
it to some parent, the popup may be removed from
that parent.

The popup can be set on one TrayIcon only. Setting the same popup on multiple TrayIcons will cause an IllegalArgumentException. 
Note: Some platforms may not support
showing the user-specified popup menu component when the user
right-clicks the tray icon.  In this situation, either no menu
will be displayed or, on some systems, a native version of the
menu may be displayed.

Params:
  • popup – a PopupMenu or null to
remove any popup menu
Throws:
See Also:
/**
     * Sets the popup menu for this <code>TrayIcon</code>.  If
     * <code>popup</code> is <code>null</code>, no popup menu will be
     * associated with this <code>TrayIcon</code>.
     *
     * <p>Note that this <code>popup</code> must not be added to any
     * parent before or after it is set on the tray icon.  If you add
     * it to some parent, the <code>popup</code> may be removed from
     * that parent.
     *
     * <p>The {@code popup} can be set on one {@code TrayIcon} only.
     * Setting the same popup on multiple {@code TrayIcon}s will cause
     * an {@code IllegalArgumentException}.
     *
     * <p><strong>Note:</strong> Some platforms may not support
     * showing the user-specified popup menu component when the user
     * right-clicks the tray icon.  In this situation, either no menu
     * will be displayed or, on some systems, a native version of the
     * menu may be displayed.
     *
     * @throws IllegalArgumentException if the {@code popup} is already
     * set for another {@code TrayIcon}
     * @param popup a <code>PopupMenu</code> or <code>null</code> to
     * remove any popup menu
     * @see #getPopupMenu
     */
    public void setPopupMenu(PopupMenu popup) {
        if (popup == this.popup) {
            return;
        }
        synchronized (TrayIcon.class) {
            if (popup != null) {
                if (popup.isTrayIconPopup) {
                    throw new IllegalArgumentException("the PopupMenu is already set for another TrayIcon");
                }
                popup.isTrayIconPopup = true;
            }
            if (this.popup != null) {
                this.popup.isTrayIconPopup = false;
            }
            this.popup = popup;
        }
    }

    
Returns the popup menu associated with this TrayIcon.

See Also:
Returns:the popup menu or null if none exists
/**
     * Returns the popup menu associated with this <code>TrayIcon</code>.
     *
     * @return the popup menu or <code>null</code> if none exists
     * @see #setPopupMenu(PopupMenu)
     */
    public PopupMenu getPopupMenu() {
        return popup;
    }

    
Sets the tooltip string for this TrayIcon. The
tooltip is displayed automatically when the mouse hovers over
the icon.  Setting the tooltip to null removes any
tooltip text.
When displayed, the tooltip string may be truncated on some platforms;
the number of characters that may be displayed is platform-dependent.

Params:
  • tooltip – the string for the tooltip; if the value is
null no tooltip is shown
See Also:
/**
     * Sets the tooltip string for this <code>TrayIcon</code>. The
     * tooltip is displayed automatically when the mouse hovers over
     * the icon.  Setting the tooltip to <code>null</code> removes any
     * tooltip text.
     *
     * When displayed, the tooltip string may be truncated on some platforms;
     * the number of characters that may be displayed is platform-dependent.
     *
     * @param tooltip the string for the tooltip; if the value is
     * <code>null</code> no tooltip is shown
     * @see #getToolTip
     */
    public void setToolTip(String tooltip) {
        this.tooltip = tooltip;

        TrayIconPeer peer = this.peer;
        if (peer != null) {
            peer.setToolTip(tooltip);
        }
    }

    
Returns the tooltip string associated with this
TrayIcon.

See Also:
Returns:the tooltip string or null if none exists
/**
     * Returns the tooltip string associated with this
     * <code>TrayIcon</code>.
     *
     * @return the tooltip string or <code>null</code> if none exists
     * @see #setToolTip(String)
     */
    public String getToolTip() {
        return tooltip;
    }

    
Sets the auto-size property.  Auto-size determines whether the
tray image is automatically sized to fit the space allocated
for the image on the tray.  By default, the auto-size property
is set to false.

 If auto-size is false, and the image size
doesn't match the tray icon space, the image is painted as-is
inside that space — if larger than the allocated space, it will
be cropped.

 If auto-size is true, the image is stretched or shrunk to
fit the tray icon space.

Params:
  • autosize – true to auto-size the image,
false otherwise
See Also:
/**
     * Sets the auto-size property.  Auto-size determines whether the
     * tray image is automatically sized to fit the space allocated
     * for the image on the tray.  By default, the auto-size property
     * is set to <code>false</code>.
     *
     * <p> If auto-size is <code>false</code>, and the image size
     * doesn't match the tray icon space, the image is painted as-is
     * inside that space &#151; if larger than the allocated space, it will
     * be cropped.
     *
     * <p> If auto-size is <code>true</code>, the image is stretched or shrunk to
     * fit the tray icon space.
     *
     * @param autosize <code>true</code> to auto-size the image,
     * <code>false</code> otherwise
     * @see #isImageAutoSize
     */
    public void setImageAutoSize(boolean autosize) {
        this.autosize = autosize;

        TrayIconPeer peer = this.peer;
        if (peer != null) {
            peer.updateImage();
        }
    }

    
Returns the value of the auto-size property.

See Also:
Returns:true if the image will be auto-sized,
false otherwise
/**
     * Returns the value of the auto-size property.
     *
     * @return <code>true</code> if the image will be auto-sized,
     * <code>false</code> otherwise
     * @see #setImageAutoSize(boolean)
     */
    public boolean isImageAutoSize() {
        return autosize;
    }

    
Adds the specified mouse listener to receive mouse events from
this TrayIcon.  Calling this method with a
null value has no effect.

Note: The MouseEvent's coordinates (received from the TrayIcon) are relative to the screen, not the TrayIcon. 
 Note: The MOUSE_ENTERED and
MOUSE_EXITED mouse events are not supported.

Refer to AWT Threading Issues for details on AWT's threading model.

Params:
  • listener – the mouse listener
See Also:
/**
     * Adds the specified mouse listener to receive mouse events from
     * this <code>TrayIcon</code>.  Calling this method with a
     * <code>null</code> value has no effect.
     *
     * <p><b>Note</b>: The {@code MouseEvent}'s coordinates (received
     * from the {@code TrayIcon}) are relative to the screen, not the
     * {@code TrayIcon}.
     *
     * <p> <b>Note: </b>The <code>MOUSE_ENTERED</code> and
     * <code>MOUSE_EXITED</code> mouse events are not supported.
     * <p>Refer to <a href="doc-files/AWTThreadIssues.html#ListenersThreads"
     * >AWT Threading Issues</a> for details on AWT's threading model.
     *
     * @param    listener the mouse listener
     * @see      java.awt.event.MouseEvent
     * @see      java.awt.event.MouseListener
     * @see      #removeMouseListener(MouseListener)
     * @see      #getMouseListeners
     */
    public synchronized void addMouseListener(MouseListener listener) {
        if (listener == null) {
            return;
        }
        mouseListener = AWTEventMulticaster.add(mouseListener, listener);
    }

    
Removes the specified mouse listener.  Calling this method with
null or an invalid value has no effect.

Refer to AWT Threading Issues for details on AWT's threading model.

Params:
  • listener –   the mouse listener
See Also:
/**
     * Removes the specified mouse listener.  Calling this method with
     * <code>null</code> or an invalid value has no effect.
     * <p>Refer to <a href="doc-files/AWTThreadIssues.html#ListenersThreads"
     * >AWT Threading Issues</a> for details on AWT's threading model.
     *
     * @param    listener   the mouse listener
     * @see      java.awt.event.MouseEvent
     * @see      java.awt.event.MouseListener
     * @see      #addMouseListener(MouseListener)
     * @see      #getMouseListeners
     */
    public synchronized void removeMouseListener(MouseListener listener) {
        if (listener == null) {
            return;
        }
        mouseListener = AWTEventMulticaster.remove(mouseListener, listener);
    }

    
Returns an array of all the mouse listeners
registered on this TrayIcon.

See Also:
Returns:all of the MouseListeners registered on
this TrayIcon or an empty array if no mouse
listeners are currently registered
/**
     * Returns an array of all the mouse listeners
     * registered on this <code>TrayIcon</code>.
     *
     * @return all of the <code>MouseListeners</code> registered on
     * this <code>TrayIcon</code> or an empty array if no mouse
     * listeners are currently registered
     *
     * @see      #addMouseListener(MouseListener)
     * @see      #removeMouseListener(MouseListener)
     * @see      java.awt.event.MouseListener
     */
    public synchronized MouseListener[] getMouseListeners() {
        return AWTEventMulticaster.getListeners(mouseListener, MouseListener.class);
    }

    
Adds the specified mouse listener to receive mouse-motion
events from this TrayIcon.  Calling this method
with a null value has no effect.

Note: The MouseEvent's coordinates (received from the TrayIcon) are relative to the screen, not the TrayIcon. 
 Note: The MOUSE_DRAGGED mouse event is not supported.

Refer to AWT Threading Issues for details on AWT's threading model.

Params:
  • listener –   the mouse listener
See Also:
/**
     * Adds the specified mouse listener to receive mouse-motion
     * events from this <code>TrayIcon</code>.  Calling this method
     * with a <code>null</code> value has no effect.
     *
     * <p><b>Note</b>: The {@code MouseEvent}'s coordinates (received
     * from the {@code TrayIcon}) are relative to the screen, not the
     * {@code TrayIcon}.
     *
     * <p> <b>Note: </b>The <code>MOUSE_DRAGGED</code> mouse event is not supported.
     * <p>Refer to <a href="doc-files/AWTThreadIssues.html#ListenersThreads"
     * >AWT Threading Issues</a> for details on AWT's threading model.
     *
     * @param    listener   the mouse listener
     * @see      java.awt.event.MouseEvent
     * @see      java.awt.event.MouseMotionListener
     * @see      #removeMouseMotionListener(MouseMotionListener)
     * @see      #getMouseMotionListeners
     */
    public synchronized void addMouseMotionListener(MouseMotionListener listener) {
        if (listener == null) {
            return;
        }
        mouseMotionListener = AWTEventMulticaster.add(mouseMotionListener, listener);
    }

    
Removes the specified mouse-motion listener.  Calling this method with
null or an invalid value has no effect.

Refer to AWT Threading Issues for details on AWT's threading model.

Params:
  • listener –   the mouse listener
See Also:
/**
     * Removes the specified mouse-motion listener.  Calling this method with
     * <code>null</code> or an invalid value has no effect.
     * <p>Refer to <a href="doc-files/AWTThreadIssues.html#ListenersThreads"
     * >AWT Threading Issues</a> for details on AWT's threading model.
     *
     * @param    listener   the mouse listener
     * @see      java.awt.event.MouseEvent
     * @see      java.awt.event.MouseMotionListener
     * @see      #addMouseMotionListener(MouseMotionListener)
     * @see      #getMouseMotionListeners
     */
    public synchronized void removeMouseMotionListener(MouseMotionListener listener) {
        if (listener == null) {
            return;
        }
        mouseMotionListener = AWTEventMulticaster.remove(mouseMotionListener, listener);
    }

    
Returns an array of all the mouse-motion listeners
registered on this TrayIcon.

See Also:
Returns:all of the MouseInputListeners registered on
this TrayIcon or an empty array if no mouse
listeners are currently registered
/**
     * Returns an array of all the mouse-motion listeners
     * registered on this <code>TrayIcon</code>.
     *
     * @return all of the <code>MouseInputListeners</code> registered on
     * this <code>TrayIcon</code> or an empty array if no mouse
     * listeners are currently registered
     *
     * @see      #addMouseMotionListener(MouseMotionListener)
     * @see      #removeMouseMotionListener(MouseMotionListener)
     * @see      java.awt.event.MouseMotionListener
     */
    public synchronized MouseMotionListener[] getMouseMotionListeners() {
        return AWTEventMulticaster.getListeners(mouseMotionListener, MouseMotionListener.class);
    }

    
Returns the command name of the action event fired by this tray icon.

See Also:
Returns:the action command name, or null if none exists
/**
     * Returns the command name of the action event fired by this tray icon.
     *
     * @return the action command name, or <code>null</code> if none exists
     * @see #addActionListener(ActionListener)
     * @see #setActionCommand(String)
     */
    public String getActionCommand() {
        return actionCommand;
    }

    
Sets the command name for the action event fired by this tray
icon.  By default, this action command is set to
null.

Params:
  • command –  a string used to set the tray icon's
                action command.
See Also:
/**
     * Sets the command name for the action event fired by this tray
     * icon.  By default, this action command is set to
     * <code>null</code>.
     *
     * @param command  a string used to set the tray icon's
     *                 action command.
     * @see java.awt.event.ActionEvent
     * @see #addActionListener(ActionListener)
     * @see #getActionCommand
     */
    public void setActionCommand(String command) {
        actionCommand = command;
    }

    
Adds the specified action listener to receive
ActionEvents from this TrayIcon.
Action events usually occur when a user selects the tray icon,
using either the mouse or keyboard.  The conditions in which
action events are generated are platform-dependent.

Calling this method with a null value has no
effect.

Refer to AWT Threading Issues for details on AWT's threading model.

Params:
  • listener – the action listener
See Also:
/**
     * Adds the specified action listener to receive
     * <code>ActionEvent</code>s from this <code>TrayIcon</code>.
     * Action events usually occur when a user selects the tray icon,
     * using either the mouse or keyboard.  The conditions in which
     * action events are generated are platform-dependent.
     *
     * <p>Calling this method with a <code>null</code> value has no
     * effect.
     * <p>Refer to <a href="doc-files/AWTThreadIssues.html#ListenersThreads"
     * >AWT Threading Issues</a> for details on AWT's threading model.
     *
     * @param         listener the action listener
     * @see           #removeActionListener
     * @see           #getActionListeners
     * @see           java.awt.event.ActionListener
     * @see #setActionCommand(String)
     */
    public synchronized void addActionListener(ActionListener listener) {
        if (listener == null) {
            return;
        }
        actionListener = AWTEventMulticaster.add(actionListener, listener);
    }

    
Removes the specified action listener.  Calling this method with
null or an invalid value has no effect.

Refer to AWT Threading Issues for details on AWT's threading model.

Params:
  • listener –   the action listener
See Also:
/**
     * Removes the specified action listener.  Calling this method with
     * <code>null</code> or an invalid value has no effect.
     * <p>Refer to <a href="doc-files/AWTThreadIssues.html#ListenersThreads"
     * >AWT Threading Issues</a> for details on AWT's threading model.
     *
     * @param    listener   the action listener
     * @see      java.awt.event.ActionEvent
     * @see      java.awt.event.ActionListener
     * @see      #addActionListener(ActionListener)
     * @see      #getActionListeners
     * @see #setActionCommand(String)
     */
    public synchronized void removeActionListener(ActionListener listener) {
        if (listener == null) {
            return;
        }
        actionListener = AWTEventMulticaster.remove(actionListener, listener);
    }

    
Returns an array of all the action listeners
registered on this TrayIcon.

See Also:
Returns:all of the ActionListeners registered on
this TrayIcon or an empty array if no action
listeners are currently registered
/**
     * Returns an array of all the action listeners
     * registered on this <code>TrayIcon</code>.
     *
     * @return all of the <code>ActionListeners</code> registered on
     * this <code>TrayIcon</code> or an empty array if no action
     * listeners are currently registered
     *
     * @see      #addActionListener(ActionListener)
     * @see      #removeActionListener(ActionListener)
     * @see      java.awt.event.ActionListener
     */
    public synchronized ActionListener[] getActionListeners() {
        return AWTEventMulticaster.getListeners(actionListener, ActionListener.class);
    }

    
The message type determines which icon will be displayed in the
caption of the message, and a possible system sound a message
may generate upon showing.

See Also:
Since:1.6
/**
     * The message type determines which icon will be displayed in the
     * caption of the message, and a possible system sound a message
     * may generate upon showing.
     *
     * @see TrayIcon
     * @see TrayIcon#displayMessage(String, String, MessageType)
     * @since 1.6
     */
    public enum MessageType {
        
An error message 
/** An error message */
        ERROR,
        
A warning message 
/** A warning message */
        WARNING,
        
An information message 
/** An information message */
        INFO,
        
Simple message 
/** Simple message */
        NONE
    };

    
Displays a popup message near the tray icon. The message will disappear after a time or if the user clicks on it. Clicking on the message may trigger an ActionEvent. 
Either the caption or the text may be null, but an
NullPointerException is thrown if both are
null.
When displayed, the caption or text strings may be truncated on
some platforms; the number of characters that may be displayed is
platform-dependent.

Note: Some platforms may not support
showing a message.

Params:
  • caption – the caption displayed above the text, usually in
bold; may be null
  • text – the text displayed for the particular message; may be
null
  • messageType – an enum indicating the message type
Throws:
/**
     * Displays a popup message near the tray icon.  The message will
     * disappear after a time or if the user clicks on it.  Clicking
     * on the message may trigger an {@code ActionEvent}.
     *
     * <p>Either the caption or the text may be <code>null</code>, but an
     * <code>NullPointerException</code> is thrown if both are
     * <code>null</code>.
     *
     * When displayed, the caption or text strings may be truncated on
     * some platforms; the number of characters that may be displayed is
     * platform-dependent.
     *
     * <p><strong>Note:</strong> Some platforms may not support
     * showing a message.
     *
     * @param caption the caption displayed above the text, usually in
     * bold; may be <code>null</code>
     * @param text the text displayed for the particular message; may be
     * <code>null</code>
     * @param messageType an enum indicating the message type
     * @throws NullPointerException if both <code>caption</code>
     * and <code>text</code> are <code>null</code>
     */
    public void displayMessage(String caption, String text, MessageType messageType) {
        if (caption == null && text == null) {
            throw new NullPointerException("displaying the message with both caption and text being null");
        }

        TrayIconPeer peer = this.peer;
        if (peer != null) {
            peer.displayMessage(caption, text, messageType.name());
        }
    }

    
Returns the size, in pixels, of the space that the tray icon occupies in the system tray. For the tray icon that is not yet added to the system tray, the returned size is equal to the result of the SystemTray.getTrayIconSize. 
See Also:
Returns:the size of the tray icon, in pixels
/**
     * Returns the size, in pixels, of the space that the tray icon
     * occupies in the system tray.  For the tray icon that is not yet
     * added to the system tray, the returned size is equal to the
     * result of the {@link SystemTray#getTrayIconSize}.
     *
     * @return the size of the tray icon, in pixels
     * @see TrayIcon#setImageAutoSize(boolean)
     * @see java.awt.Image
     * @see TrayIcon#getSize()
     */
    public Dimension getSize() {
        return SystemTray.getSystemTray().getTrayIconSize();
    }

    // ****************************************************************
    // ****************************************************************

    void addNotify()
      throws AWTException
    {
        synchronized (this) {
            if (peer == null) {
                Toolkit toolkit = Toolkit.getDefaultToolkit();
                if (toolkit instanceof SunToolkit) {
                    peer = ((SunToolkit)Toolkit.getDefaultToolkit()).createTrayIcon(this);
                } else if (toolkit instanceof HeadlessToolkit) {
                    peer = ((HeadlessToolkit)Toolkit.getDefaultToolkit()).createTrayIcon(this);
                }
            }
        }
        peer.setToolTip(tooltip);
    }

    void removeNotify() {
        TrayIconPeer p = null;
        synchronized (this) {
            p = peer;
            peer = null;
        }
        if (p != null) {
            p.dispose();
        }
    }

    void setID(int id) {
        this.id = id;
    }

    int getID(){
        return id;
    }

    void dispatchEvent(AWTEvent e) {
        EventQueue.setCurrentEventAndMostRecentTime(e);
        Toolkit.getDefaultToolkit().notifyAWTEventListeners(e);
        processEvent(e);
    }

    void processEvent(AWTEvent e) {
        if (e instanceof MouseEvent) {
            switch(e.getID()) {
            case MouseEvent.MOUSE_PRESSED:
            case MouseEvent.MOUSE_RELEASED:
            case MouseEvent.MOUSE_CLICKED:
                processMouseEvent((MouseEvent)e);
                break;
            case MouseEvent.MOUSE_MOVED:
                processMouseMotionEvent((MouseEvent)e);
                break;
            default:
                return;
            }
        } else if (e instanceof ActionEvent) {
            processActionEvent((ActionEvent)e);
        }
    }

    void processMouseEvent(MouseEvent e) {
        MouseListener listener = mouseListener;

        if (listener != null) {
            int id = e.getID();
            switch(id) {
            case MouseEvent.MOUSE_PRESSED:
                listener.mousePressed(e);
                break;
            case MouseEvent.MOUSE_RELEASED:
                listener.mouseReleased(e);
                break;
            case MouseEvent.MOUSE_CLICKED:
                listener.mouseClicked(e);
                break;
            default:
                return;
            }
        }
    }

    void processMouseMotionEvent(MouseEvent e) {
        MouseMotionListener listener = mouseMotionListener;
        if (listener != null &&
            e.getID() == MouseEvent.MOUSE_MOVED)
        {
            listener.mouseMoved(e);
        }
    }

    void processActionEvent(ActionEvent e) {
        ActionListener listener = actionListener;
        if (listener != null) {
            listener.actionPerformed(e);
        }
    }

    private static native void initIDs();
}