title: serialVersionUID field warning in eclipse
body: <p>I have just started on AWT and made a simple program in it, it works fine but it shows a warning message in eclipse which i don't understand:</p>
  
  <blockquote>
    <p>The serializable class TestGUI does not declare a static final
    serialVersionUID field of type long</p>
  </blockquote>
  
  <p>I know that the warning message is not related to AWT and there was no need to post my whole code but when i tried to make a SSCCE of the code the warning also disappeared. Since I don't know why this warning is generated i didn't knew which part to retain in my SSCCE. Hence the whole code!</p>
  
  <p>My code is:</p>
  
  <pre><code>import java.awt.Frame;
  import java.awt.Graphics;
  import java.awt.event.MouseAdapter;
  import java.awt.event.MouseEvent;
  import java.awt.event.WindowAdapter;
  import java.awt.event.WindowEvent;
  
  public class TestGUI extends Frame {
      /**
       * @param args
       */
      private int x = 50;
      private int y = 50;
  
      TestGUI(String s) {
          addWindowListener(new WindowAdapter() {
              public void windowClosing(WindowEvent we) {
                  setVisible(false);
                  System.exit(0);
              }
          });
          addMouseListener(new MouseAdapter() {
              public void mouseClicked(MouseEvent me) {
                  x = me.getX();
                  y = me.getY();
                  repaint();
              }
          });
      }
  
      public void paint(Graphics g) {
          g.drawString("Hello Princess", 100, 100);
          g.drawString("Mouse clicked here", x, y);
      }
  
      public static void main(String[] args) {
          // TODO Auto-generated method stub
          TestGUI tg = new TestGUI("first");
          tg.setSize(500, 500);
          tg.setVisible(true);
      }
  
  }
  </code></pre>
  
  <p>Thanx in advance!</p>