Java Alley | The New AWT Event Model in Java 1.1 (Web Techniques, Aug 1997)

//: DynamicEvents.java
 * The new Java 1.1 event model allows you to
 * change event behavior dynamically. Also
 * demonstrates multiple actions for an event.
import java.awt.*;
import java.awt.event.*;
import java.util.*;
public class DynamicEvents extends Frame {
  Vector v = new Vector();
  int i = 0;
  Button 
    b1 = new Button("Button 1"), 
    b2 = new Button("Button 2");
  public DynamicEvents() {
    addWindowListener(new BWL());
    setLayout(new FlowLayout());
    b1.addActionListener(new B());
    b1.addActionListener(new B1());
    b2.addActionListener(new B());
    b2.addActionListener(new B2());
    add(b1);
    add(b2);
  class B implements ActionListener {
    public void actionPerformed(ActionEvent e) {
      System.out.println("A button was pressed");
    }
  class CountListener implements ActionListener {
    int index;
    public CountListener(int i) { index = i; }
    public void actionPerformed(ActionEvent e) {
      System.out.println(
        "Counted Listener " + index);
    }
  }    
  class B1 implements ActionListener {
    public void actionPerformed(ActionEvent e) {
      System.out.println("Button 1 pressed");
      ActionListener a = new CountListener(i++);
      v.addElement(a);
      b2.addActionListener(a);
    }
  class B2 implements ActionListener {
    public void actionPerformed(ActionEvent e) {
      System.out.println("Button 2 pressed");
      int end = v.size() -1;
      if(end >= 0) {
        b2.removeActionListener(
          (ActionListener)v.elementAt(end));
        v.removeElementAt(end);
      }
    }
  class BWL extends WindowAdapter {
    public void windowClosing(WindowEvent e) {
      System.out.println("Window Closing");
      System.exit(0);
    }
  public static void main(String args[]) {
    Frame f = new DynamicEvents();
    f.setSize(300,200);
    f.show();
} ///:~