welcome.java

一个用java多线程实现的applet小程序

import java.awt.*;
import java.awt.event.*;

public class Welcome extends WindowAdapter implements ActionListener
    {

      Frame f;
      static Welcome.Thread3 wt1,wt2;
      
      public static void main(String args[])
         {

           Welcome w = new Welcome();
           w.display();
           wt1 = w.new Thread3("Welcome!");
           wt2 = w.new Thread3("How are you?");
           wt2.start();
           wt2.setButton();

          }

           public void display()
      
             {

               f = new Frame("Welcome");
               f.setSize(400,240);
               f.setLocation(200,140);
               f.setBackground(Color.lightGray);
               f.setLayout(new GridLayout(4,1));
               f.addWindowListener(this);
               f.setVisible(true);

              }

            public class Thread3 extends Thread
              {

                Panel p1;
                Label lb1;
                TextField tf1,tf2;
                Button b1,b2;
                int sleeptime = (int)(Math.random()*100);
              
                public Thread3(String str)
                  {

                    super(str);
                    for(int i=0;i<100;i++)
                        str=str+" ";
                    tf1 = new TextField(str);
                    f.add(tf1);
                    p1 = new Panel();
                    p1.setLayout(new FlowLayout(FlowLayout.LEFT));
                    lb1 = new Label("sleep");
                    tf2 = new TextField(""+sleeptime);
                    p1.add(lb1);
                    p1.add(tf2);
                    b1 = new Button("启动");
                    b2 = new Button("中断");
                    p1.add(b1);
                    p1.add(b2);
                    b1.addActionListener(new Welcome());
                    b2.addActionListener(new Welcome());
                    f.add(p1);
                    f.setVisible(true);

                   }

                 public void run()
                   {

                     String str;
                     while(this.isAlive()&&!this.isInterrupted())
                        {
                          try
                            {
                              str=tf1.getText();
                              str=str.substring(1)+str.substring(0,1);
                              tf1.setText(str);
                              this.sleep(sleeptime);
                             }

                           catch(InterruptedException e)
                             {
                               System.out.println(e);
                               break;
                             }
                          }
                      }

                    public void setButton()
                      {

                        if(this.isAlive())  b1.setEnabled(false);
                        if(this.isInterrupted())  b2.setEnabled(false);
                       }
                 }

               public void windowClosing(WindowEvent e)
                 {

                    System.exit(0);

                  }

                public void actionPerformed(ActionEvent e)
                  {

                     if((e.getSource()==wt1.b1)||(e.getSource()==wt1.b2))
                        actionPerformed(e,wt1);
                     if((e.getSource()==wt2.b1)||(e.getSource()==wt2.b2))
                        actionPerformed(e,wt2);
                   }

                 public void actionPerformed(ActionEvent e,Thread3 wt1)
                   {

                     if(e.getSource()==wt1.b1)
                        {
                          wt1.sleeptime=Integer.parseInt(wt1.tf2.getText());
                          wt1.start();
                        }
                      if(e.getSource()==wt1.b2)
                        wt1.interrupt();
                      wt1.setButton();
                    }
            }