{ while(distance>=10&&distance<100) try{ wait(); } catch(Exception exp){} distance=distance+1; b.setLocation(distance,60); if(distance>200) { distance=10; b.setLocation(100,60); notifyAll(); } } } } MoveButtonMainClass.java public class MoveButtonMainClass { public static void main(String args[]) { new MoveButton(); } }
练习：在MoveButton类中再增加一个蓝色的按钮和一个third线程，third线程负责将这个蓝色的按钮从（200，60）运动到（300，60）。 MoveButton.java import java.awt.*; import java.awt.event.*; public class MoveButton extends Frame implements Runnable,ActionListener { /** * */ private static final long serialVersionUID = 1L; Thread first,second,third;//【补充代码】 //用Thread类声明first,second两个线程对象 Button redButton,greenButton,blueButton,startButton; int distance=10; MoveButton() { first=new Thread(this);//【补充代码】 //创建first线程，当前窗口做为该线程的目标对象 second=new Thread(this);//【补充代码】 //创建first线程，当前窗口做为该线程的目标对象 third=new Thread(this); redButton=new Button(); greenButton=new Button(); blueButton=new Button(); redButton.setBackground(Color.red); greenButton.setBackground(Color.green); blueButton.setBackground(Color.blue); startButton=new Button(\); startButton.addActionListener(this); setLayout(null); add(redButton); redButton.setBounds(10,60,15,15); add(greenButton); greenButton.setBounds(100,60,15,15); add(blueButton); blueButton.setBounds(200,60, 15, 15); add(startButton); startButton.setBounds(10,100,30,30); setBounds(0,0,350,200); setVisible(true); validate(); addWindowListener(new WindowAdapter() { public void windowClosing(WindowEvent e) { System.exit(0); } } ); } public void actionPerformed(ActionEvent e) { try{ first.start(); second.start(); third.start(); } catch(Exception exp){} } public void run() { while(true) { if(Thread.currentThread()==first) //判断当前占有CPU资源的线程是否是first { moveComponent(redButton); try{ Thread.sleep(20); } catch(Exception exp){} } if(Thread.currentThread()==second) //判断当前占有CPU资源的线程是否是second { moveComponent(greenButton); try{ Thread.sleep(10); } catch(Exception exp){} } if(Thread.currentThread()==third) { moveComponent(blueButton); try{Thread.sleep(50); } catch(Exception exp){} } } } public synchronized void moveComponent(Component b) { if(Thread.currentThread()==first) { while(distance>100&&distance<=300) try{ wait(); } catch(Exception exp){} distance=distance+1; b.setLocation(distance,60); if(distance>=100) { b.setLocation(10,60); notifyAll(); } } if(Thread.currentThread()==second) { while(distance>=10&&distance<100) try{ wait();