The SystemTray class represents the system tray for a desktop. On Microsoft Windows it is referred to as the "Taskbar Status Area", on Gnome it is referred to as the "Notification Area", on KDE it is referred to as the "System Tray". The system tray is shared by all applications running on the desktop.

On some platforms the system tray may not be present or may not be supported, in this case SystemTray.getSystemTray() throws UnsupportedOperationException. To detect whether the system tray is supported, use SystemTray.isSupported.

The SystemTray may contain one or more TrayIcons, which are added to the tray using the add method, and removed when no longer needed, using the remove. TrayIcon consists of an image, a popup menu and a set of associated listeners. Please see the TrayIcon class for details.

Every Java application has a single SystemTray instance that allows the app to interface with the system tray of the desktop while the app is running. The SystemTray instance can be obtained from the getSystemTray method. An application may not create its own instance of SystemTray.

The following code snippet demonstrates how to access and customize the system tray:

 
     TrayIcon trayIcon = null;
     if (SystemTray.isSupported()) {
         // get the SystemTray instance
         SystemTray tray = SystemTray.getSystemTray;
         // load an image
         java.awt.Image image = Toolkit.getDefaultToolkit().getImage(...);
         // create a action listener to listen for default action executed on the tray icon
         java.awt.event.ActionListener listener = new ActionListener() {
             public void actionPerformed(java.awt.event.ActionEvent e) {
                 // execute default action of the application
                 // ...
             }
         };
         // create a popup menu
         java.awt.PopupMenu popup = new PopupMenu();
         // create menu item for the default action
         MenuItem defaultItem = new MenuItem(...);
         defaultItem.addActionListener(listener);
         popup.add(defaultItem);
         /// ... add other items
         // construct a TrayIcon
         trayIcon = new TrayIcon(image, "Tray Demo", popup);
         // set the TrayIcon properties
         trayIcon.addActionListener(listener);
         // ...
         // add the tray image
         try {
             tray.add(trayIcon);
         } catch (AWTException e) {
             System.err.println(e);
         }
         // ...
     } else {
         // disable tray option in your application or
         // perform other actions
         ...
     }
     // ...
     // some time later
     // the application state has changed - update the image
     if (trayIcon != null) {
         trayIcon.setImage(updatedImage);
     }
     // ...