main.java

自定义接口的使用,输入年份,求一个人的年龄.

/*
 * Main.java
 *
 * Created on 2007年11月24日, 下午1:26
 *
 * To change this template, choose Tools | Template Manager
 * and open the template in the editor.
 */

package exp3;
import java.util.Calendar;
import java.awt.*;
import java.awt.event.*;

/**
 *
 * @author Administrator
 */
public class Main {
    
    /** Creates a new instance of Main */
    public Main() {
    }
    
    /**
     * @param args the command line arguments
     */
    public static void main(String[] args) {
       new FrameInOut(); 
    }
    
}


abstract interface Getage{
   public int Age();}

class closewindow extends WindowAdapter{
   public void windowClosing(WindowEvent e)
   {
        Frame  frm=(Frame)(e.getSource());
        frm.dispose();
        System.exit(0);
   }
}
class FrameInOut extends Frame implements ActionListener,Getage{
   public int Age(){
       Calendar   ca=Calendar.getInstance();   
  int year=ca.get(Calendar.YEAR);
  String s=input.getText();
  int yearborn=Integer.valueOf(s).intValue();
  int hisage=year-yearborn;
   return hisage;}
    
    
    Label prompt1,prompt2;
TextField input,output;
Button btn1,btn2;
FrameInOut(){
super("计算年龄");
prompt1=new Label("请输入出生年份:");
prompt2=new Label("       结果:             ");
input=new TextField(10);
output=new TextField(15);
btn1=new Button("确定");
btn2=new Button("关闭");
setLayout(new FlowLayout());
add(prompt1);
add(input);
add(prompt2);
add(output);
add(btn1);
add(btn2);
addWindowListener(new closewindow());
btn1.addActionListener(this);
btn2.addActionListener(this);
setSize(250,150);
show();
}
public void actionPerformed(ActionEvent e){
if(e.getSource()==btn1){
    output.setText("此人的年龄为:"+Age());
}
else{
dispose();
System.exit(0);}
}
}