5 kinds of event handler styles

依處理器所掛的位置,總共有5種寫法,以計時器處理器為例,
A.處理器掛在外部類別下:
 
 import javax.swing.Timer;
 import java.awt.event.ActionListener;
 import java.awt.event.ActionEvent;
 public class TimerTest1
 {
   public static void main(String args[]) throws Exception
   {
     ActionListener al = new TimerHandler();
     Timer t = new Timer(1000,al);
     t.start();
     Thread.sleep(10000);
     t.stop();
   }
 }
 
class TimerHandler implements ActionListener
 {
   public void actionPerformed(ActionEvent ae)
   {
     System.out.println("執行每次叫醒要作的事1");
   }
 }

B.處理器掛在內部匿名類別下:
 
 import javax.swing.Timer;
 import java.awt.event.ActionListener;
 import java.awt.event.ActionEvent;
 public class TimerTest2
 {
   public static void main(String args[]) throws Exception
   {
     ActionListener al = new ActionListener()
       {
  public void actionPerformed(ActionEvent ae)
  {
    System.out.println("執行每次叫醒要作的事2");
  }
       };
     Timer t = new Timer(1000,al);
     t.start();
     Thread.sleep(10000);
     t.stop();
   }
 }

C.處理器掛在內部有名類別下:
 
 import javax.swing.Timer;
 import java.awt.event.ActionListener;
 import java.awt.event.ActionEvent;
 public class TimerTest3
 {
   public static void main(String args[]) throws Exception
   {
     new TimerTest3();
   }
 
   TimerTest3() throws Exception
   {
     ActionListener al = new TimerHandler();
     Timer t = new Timer(1000,al);
     t.start();
     Thread.sleep(10000);
     t.stop();
   }
 
   private class TimerHandler implements ActionListener
   {
     public void actionPerformed(ActionEvent ae)
     {
       System.out.println("執行每次叫醒要作的事3");
     }
   }
 }

D.處理器掛在本身類別下:
 
 import javax.swing.Timer;
 import java.awt.event.ActionListener;
 import java.awt.event.ActionEvent;
 public class TimerTest4 implements ActionListener
 {
   public void actionPerformed(ActionEvent ae)
   {
     System.out.println("執行每次叫醒要作的事4");
   }
 
   public static void main(String args[]) throws Exception
   {
     ActionListener al = new TimerTest4();
     Timer t = new Timer(1000,al);
     t.start();
     Thread.sleep(10000);
     t.stop();
   }
 }

E.處理器同時掛在內部和外部類別下:
 
 import javax.swing.Timer;
 import java.awt.event.ActionListener;
 import java.awt.event.ActionEvent;
 public class TimerTest5
 {
   public static void main(String args[]) throws Exception
   {
     ActionListener al = new ActionAdapter()
       {
  public void actionPerformed(ActionEvent ae)
  {
    System.out.println("執行每次叫醒要作的事5x");
  }
       };
     Timer t = new Timer(1000,al);
     t.start();
     Thread.sleep(10000);
     t.stop();
   }
 }
 
 class ActionAdapter implements ActionListener
 {
   public void actionPerformed(ActionEvent ae)
   {
     System.out.println("執行每次叫醒要作的事5");
   }
 }