Tray and Notifications Sample

import java.awt.AWTException;
import java.awt.MenuItem;
import java.awt.PopupMenu;
import java.awt.SystemTray;
import java.awt.TrayIcon;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.io.File;
import java.io.IOException;
import javax.imageio.ImageIO;
import javax.swing.JOptionPane

public class Main {
   public static void main(String[] args) throws AWTException, IOException {
       if (SystemTray.isSupported()) {
           JOptionPane.showMessageDialog(null, "Eu suporto SystemTray ");

           SystemTray tray = SystemTray.getSystemTray();
           tray.add(new MyTrayIcon());

       }

   }
}

class MyTrayIcon extends TrayIcon {
   public MyTrayIcon() throws IOException {
       super(ImageIO.read(new File("img.jpg")), "TrayIcon ");
       setImageAutoSize(true);
       final PopupMenu popup = new PopupMenu("popup");
       setPopupMenu(popup);
       getPopupMenu().add(new MenuItem("menuItem"));
       addMouseListener(new MouseAdapter() {
           @Override
           public void mouseClicked(MouseEvent e) {
               displayMessage("Finished downloading", "Your Java application has finished downloading", TrayIcon.MessageType.INFO);
           }
       });
   }
}