testinginner.java

java的书上例子

//例12_11  用内部类实现了监听器接口
import java.awt.*;
import java.awt.event.*;

public class TestingInner{
   private Frame f=new Frame();
   private TextArea text=new TextArea();
   private Button b1=new Button("Button1");
   private Button b2=new Button("Button2");
   private Button b3=new Button("Button3");
   private Button b4=new Button("Button4");
   private String fileName="";  
   
   public TestingInner(){
        f.setLayout(new BorderLayout());
        f.addWindowListener(new WindowClosing());
		b1.addActionListener(new ButtonHandler());
		b2.addActionListener(new ButtonHandler());
        b3.addActionListener(new ButtonHandler());
        b4.addActionListener(new ButtonHandler());
        b1.setActionCommand("the Button1 was pressed");
        b2.setActionCommand("the Button2 was pressed");
        b3.setActionCommand("the Button3 was pressed");
        b4.setActionCommand("the Button4 was pressed");
        f.add("North",b1);        
        f.add("South",b2);
        f.add("West",b3);
        f.add("East",b4);
		f.add("Center",text);
        f.setSize(200,200);
        f.setVisible(true);
	}

   class ButtonHandler implements ActionListener{  
 //内部类实现了ActionListener接口
		 public void actionPerformed(ActionEvent e){
			String s=e.getActionCommand();
			text.setText(s);
		}
	}
 
 class WindowClosing extends WindowAdapter{
       //内部类继承了WindowAdapter 适配器
       public void windowClosing(WindowEvent e){
        System.exit(0);
       }
  }
public static void main(String args[]){
  TestingInner ti=new TestingInner(); 
} 
}