抛硬币模拟（Coin Tossing Simulation）

//Coin Tossing Simulation
//Java how to program, 5/e, Exercise 6.30
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
public class CoinTossing extends JApplet implements ActionListener {
 int tailNumber=0,headNumber=0;
 JLabel TossLable,TailLable,HeadLable;
 JButton TossButton;
 JTextField TailField,HeadField;

 
 public void init()
 {
     
     Container  container=getContentPane();
     container.setLayout(new FlowLayout());
     
     TossButton= new JButton("Toss");
     container.add(TossButton);
     
     
     TailLable= new JLabel("Tail frequency is:");
     container.add(TailLable);
     
     TailField=new JTextField(10);
     container.add(TailField);
     
     HeadLable= new JLabel("Head frequency is:");
     container.add(HeadLable);
     
     HeadField=new JTextField(10);
     container.add(HeadField);
     
     TossButton.addActionListener(this);
     

 }
 
 public void actionPerformed (ActionEvent event)
 {
         if (Flip())
             tailNumber++;
         else
             headNumber++;
        
    TailField.setText(Integer.toString(tailNumber));
    HeadField.setText(Integer.toString(headNumber));

 }
 
 public boolean Flip()
 {
     return Math.random()<0.5;
 }
}