title: Swing FocusTraversalPolicy across multiple JPanels
body: <p>I have two <code>JPanel</code> objects which contain multiple components.
  Each panel has its own <code>FocusTraversalPolicy</code>.</p>
  
  <p>I want to start the focus cycle at the first component of the first panel. 
  When the focus reached the last component of the first panel the focus should jump to the first component of the second panel when I press <kbd>Tab</kbd>.</p>
  
  <p>On both panels the <code>FocusTraversalPolicyProvider</code> is enabled. </p>
  
  <p>How does this work?</p>
  
  <pre><code>public class Panel1 extends JPanel{
  
      private JTextField text1;
      private JTextField text2;
  
      public JPanel1(){
          init();
      }
  
      private void init(){
          text1 = new JTextField();
          text2 = new JTextField();
  
          this.setLayout(new FlowLayout());
          this.add(text1);
          this.add(text2);
  
          this.setFocusTraversalPolicyProvider(true);
          this.setFocusTraversalPolicy(new SimpleFocusTraversalPolicy(
              text1,
              text2
          ));
      }
  }
  
  public class Panel2 extends JPanel{
  
      private JTextField text1;
      private JTextField text2;
  
      public JPanel2(){
          init();
      }
  
      private void init(){
          text1 = new JTextField();
          text2 = new JTextField();
  
          this.setLayout(new FlowLayout());
          this.add(text1);
          this.add(text2);
  
          this.setFocusTraversalPolicyProvider(true);
          this.setFocusTraversalPolicy(new SimpleFocusTraversalPolicy(
              text1,
              text2
          ));
      }
  }
  
  public class ContainerPanel extends JPanel{
  
      private JPanel panel1, panel2;
  
      public ContainerPanel(){
          init();
      }
  
      private void init(){
          panel1 = new Panel1();
          panel2 = new Panel2();
  
          this.setLayout(new FlowLayout());
          this.add(panel1);
          this.add(panel2);
  
          /*
              what should I do here to jump from panel1 to panel2 after the last component of panel1?
          */
      }
  }
  </code></pre>