200602130300511861.java

applet编写的小应用程序,关于图形显示

//动态的显示不同色的形状图案的Applet
import java.awt.*;
import java.applet.*;
import java.util.*;
public class Applet1 extends Applet implements Runnable //javaApplet主类
{
       Thread ShapeThread = null;   //定义线程对象
       Random RandomNumber = new Random();
       Color ImageColor;   //定义COLOR对象
       public void start()
       {
           if(ShapeThread==null)
           {
                 ShapeThread = new Thread(this);   //创建线程对象
                 ShapeThread.start();
           }
       }
       public void run()  //实现RUNNABLE接口的RUN()方法
       {
           while(true)
           {
           //根据NEXTINT函数返回的随机整数模5的结果为IMAGECOLOR同赋值
           switch(RandomNumber.nextInt()%5)
           {
               case 0:ImageColor=Color.black;break;
               case 1:ImageColor=Color.blue;break;
               case 2:ImageColor=Color.cyan;break;
               case 3:ImageColor=Color.magenta;break;
               case 4:ImageColor=Color.orange;break;
               default:ImageColor=Color.red;              
           }
           try{
               ShapeThread.sleep(300);
           }
           catch(InterruptedException e){
                  //忽略异常
           }
           repaint();
           }
       }
       public void paint(Graphics g)
       {
           g.setColor(ImageColor);  //设置新的色
           switch(RandomNumber.nextInt()%2)
           {
               case 0:g.fillRect(25,25,120,200);break;   //画实心矩形
               default:g.fillOval(25,25,150,200);break;  //画实心椭圆
           }
       }
}