JAVA模仿屏保

这也是以前写的一个东西,全屏下运行,很像是WINDOWS下的屏保,会显示时钟,并且会随机自然地碰撞.全屏状态下如需退出,请按小键盘上的0退出.
点击下载可执行的JAR文件,JDK1.5以上

import  java.text. * ;
import  java.awt. * ;
import  javax.swing. * ;
import  java.awt.geom. * ;
import  java.util. * ;
import  java.awt.event. * ;
/*
 * ScreenTest.java
 *
 * Created on 2006年7月6日, 下午5:23
 *
 * To change this template, choose Tools | Template Manager
 * and open the template in the editor.
  */

/**
 *
 *  @author  lbf
  */
public   class  ScreenTest  extends  JPanel  implements  Runnable{
    
     /**  Creates a new instance of ScreenTest  */
     private  String time;
     private  Rectangle2D rd;
     private   int  x,y,a,b; // 座标值和方向值
     private   int  rgb = 0 ; // 颜色的值
     private  Color color; // 字体的颜色
     private   int  width,height; // 屏幕的大小
     public  ScreenTest( int  width, int  height) {
         this .width = width;
         this .height = height;
        initWindow();
    }
     private   void  initWindow(){
        x = ( int )(Math.random() * 300 );
        y = ( int )(Math.random() * 500 );
        a = 1 ;
        b = 1 ;
         this .setBackground(Color.BLACK);
         this .setOpaque( true );
        rd = new  Rectangle2D.Double( 10 , 10 , 101 , 10 );
        color = Color.YELLOW;
    }
     private   void  doColor(){
       rgb = ( int )(Math.random() * 0xFFFFFF );
           color = new  Color(rgb);
     }
     public   void  paintComponent(Graphics g){
        g.setColor(Color.BLACK);
        g.fillRect( 0 , 0 ,width,height);
        g.setColor(color);
        g.setFont( new  Font( " 楷书 " ,Font.BOLD, 150 ));
        FontMetrics fm = g.getFontMetrics();
        rd = fm.getStringBounds(time,g);
        g.drawString(time,x,( int )(y + rd.getHeight()));
      }
     private   void  doTime(){
        Calendar cal = Calendar.getInstance();
        DateFormat df = DateFormat.getTimeInstance(DateFormat.MEDIUM);
        Date date = cal.getTime();
        time = df.format(date);
        x += a;
        y += b;
         double  width1 = rd.getWidth();
         double  height1 = rd.getHeight();
        rd.setRect(x,y,width1,height1);
         if (rd.intersectsLine(width, 0 ,width,height)){
            doColor();
            a =- 1 ;
        }
         else   if (rd.intersectsLine( 0 , 0 , 0 ,height)){
            doColor();
            a = 1 ;
        }
         else   if (rd.getY() <=- 80 ){
             doColor();
             b = 1 ;
        }
         else   if (rd.intersectsLine( 0 ,height,width,height)){
           doColor();
            b =- 1 ;
        }
        
    }
     public   void  run(){
         while ( true ){
             try {
                Thread.sleep( 2 );
                doTime();
                repaint();
            }
             catch (InterruptedException ie){
                ie.printStackTrace();
            }
        }
    }
    public    static   void  main(String arsg[]){
        
        GraphicsDevice gd = GraphicsEnvironment.getLocalGraphicsEnvironment().getDefaultScreenDevice();
        DisplayMode dm = gd.getDisplayMode();
         int  width = dm.getWidth();
         int  height = dm.getHeight();
        System.out.println( " width= " + width + " \nheight= " + height);
        ScreenTest st = new  ScreenTest(width,height);
         final  JFrame jf = new  JFrame();
        jf.getContentPane().add(st,BorderLayout.CENTER);
        jf.setUndecorated( true );
        gd.setFullScreenWindow(jf);
         new  Thread(st).start();
        jf.addKeyListener( new  KeyAdapter(){
            public   void  keyReleased(KeyEvent ke){
                if (ke.getKeyCode() == KeyEvent.VK_NUMPAD0)
                   System.exit( 0 );
                } 
        });
    }
    
}