public class Main {
   JFrame mainFrame;
   JPanel mainPanel;
   JLabel countLabel;
   public JButton countButton;
   int pressCount;

   
   public Main() {
      //Create and set up the window.
      mainFrame = new JFrame("Sample");
   
      //Create and set up the panel.
      mainPanel = new JPanel(new GridLayout(2, 2));
      
      //Add the widgets.
      countLabel = new JLabel("0", SwingConstants.LEFT);
      countButton = new JButton("Count");
      
      //Add the widgets to the container.
      mainPanel.add(countLabel);
      mainPanel.add(countButton);

      // BEHAVIOR
      pressCount = 0;        
      countButton.addActionListener(new ActionListener() {
         public void actionPerformed(ActionEvent e) {
            pressCount++;
            countLabel.setText(""+ pressCount);
         }
      });

      //Add the panel to the window.
      mainFrame.getContentPane().add(mainPanel, BorderLayout.CENTER);
            
      //Display the window.
      mainFrame.pack();
      mainFrame.setVisible(true);
   }

While the visual aspects of the GUI can easily be generated with XML or a GUI builder, the behaviour aspects cannot. Because the behavioural aspects must be embedded in the class that lays out the GUI, it is difficult to use automatically generate the layout code: re-generating it would stomp on the behavioural code.

public aspect AddListener {
  private XTextField countField;
  private XLabel pressCount;

  after(String aName, String aLabel): execution(XButton.new(String, String)) && args(aName, aLabel)   
  {     
    if(aName == "buttonOne") 
    {       
      XButton xb = (XButton)(thisJoinPoint.getThis());       
      xb.addActionListener(new ActionListener() 
      {       
        public void actionPerformed(ActionEvent e) 
        {         
          <i>button1 action</i>;       
        });     
      }
   }   

  after(String aName, String aLabel): execution(XButton.new(String, String)) && args(aName, aLabel)   
  {     
    if(aName == "buttonTwo") 
    {       
      XButton xb = (XButton)(thisJoinPoint.getThis());       
      xb.addActionListener(new ActionListener() 
      {       
        public void actionPerformed(ActionEvent e) 
        {         
          <i>button2 action</i>;       
        });     
      }
   }   

 }  

Broadly speaking, there are two important characteristics of widgets: actions (e.g. button pushes) and state (e.g. text fields, labels). Actions can be attached to widgets once, in advice after() the widget is created. Widgets with state need to have a pointer to them kept in the state.

This structure is so regular that a skeleton can be generated automatically.