jlab0901.java

java教程中的编程实例

import java.applet.Applet;
import java.awt.*;
public class JLab0901 extends Applet{
     private int initCnt;
     private int startCnt;
     private int stopCnt;
     private int destroyCnt;
     private int paintCnt;
    public void LifeCycle(){
         initCnt=0;
         startCnt=0;
         stopCnt=0;
         destroyCnt=0;
         paintCnt=0;
           }
    public void init(){
          initCnt++;
          System.out.println("init()invoked"+initCnt+"time(s).");
            }
    public void destroy(){
          destroyCnt++;
          System.out.println("destroy()invoked"+destroyCnt+"time(s).");
            }
    public void start(){
          startCnt++;
          System.out.println("start()invoked"+startCnt+"time(s).");
            }
    public void stop(){
          stopCnt++;
          System.out.println("stop()invoked"+stopCnt+"time(s).");
            }
    public void paint(Graphics g){
            paintCnt++;
            System.out.println("paint()invoked"+paintCnt+"time(s).");
            g.drawLine(20,200,300,200);
            g.drawLine(20,200,20,20);
            g.drawLine(20,170,15,170);
            g.drawLine(20,140,15,140);
            g.drawLine(20,110,15,110);
            g.drawLine(20,80,15,80);
            g.drawLine(20,50,15,50);
            g.drawString("init()",25,213);
            g.drawString("start()",75,213);
            g.drawString("stop()",125,213);
            g.drawString("destroy()",175,213);
            g.drawString("paint()",235,213);
            g.fillRect(25,200-initCnt*30,40,initCnt*30);
            g.fillRect(75,200-startCnt*30,40,startCnt*30);
            g.fillRect(125,200-stopCnt*30,40,stopCnt*30);
            g.fillRect(175,200-destroyCnt*30,40,destroyCnt*30);
            g.fillRect(235,200-paintCnt*30,40,paintCnt*30);
           }
      }