这个程序为啥不能运行

[leeak]

//Fig 6-9:Craps.java
//Craps
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;

public class Craps extends JApplet implements ActionListener
{
final int WON=0,LOST=1,CONTINUE=2;
boolean firstRoll=true;
int sumofDice=0;
int myPoint=0;
int gameStatus=CONTINUE;

JLabel die1Label,die2Label,sumLabel,pointLabel;
JTextField firstDie,secondDie,sum,point;
JButton roll;

public void init(){
Container c=getContentPane();
c.setLayout(new FlowLayout());

die1Label=new JLabel("DIE 1");
c.add(die1Label);
firstDie=new JTextField(10);
firstDie.setEditable(false);
c.add(firstDie);

die2Label=new JLabel("Die 2");
c.add(die2Label);
secondDie=new JTextField(10);
secondDie.setEditable(false);
c.add(secondDie);

sumLabel=new JLabel("sum is");
c.add(sumLabel);
sum=new JTextField(10);
sum.setEditable(false);
c.add(sum);

pointLabel=new JLabel("point is ");
c.add(pointLabel);
point=new JTextField(10);
point.setEditable(false);
c.add(point);

roll=new JButton("Roll DICE");
roll.addActionListener(this);
c.add(roll);
}

public void actionperformed(ActionEvent e)
{
play();
}

public void play()
{
if(firstRoll){
sumofDice=rollDice();

switch (sumofDice){
case 7:case 11:
gameStatus=WON;
point.setText("");
break;
case 2:case 3: case 12:
gameStatus=LOST;
point.setText(Integer.toString(myPoint));
firstRoll=false;
}
}
else{
sumofDice=rollDice();

if (sumofDice==myPoint)
gameStatus=WON;
else
if(sumofDice==7)
gameStatus=LOST;
}
if (gameStatus==CONTINUE)
showStatus("Roll again");
else{
if(gameStatus==WON)
showStatus("player wins.click roll dice to play again");
else
showStatus("player loses.click roll Dice to play again");

firstRoll=true;
}
}

public int rollDice()
{
int die1,die2,workSum;

die1=1+(int)(Math.random()*6);
die2=1+(int)(Math.random()*6);
workSum=die1+die2;

firstDie.setText(Integer.toString(die1));
secondDie.setText(Integer.toString(die2));
sum.setText(Integer.toString(workSum));

return workSum;
}
}
运行后提示
--------------------Configuration: JDK version <Default>--------------------
C:\java1\6\U6\Craps.java:7: Craps is not abstract and does not override abstract method actionPerformed(java.awt.event.ActionEvent) in java.awt.event.ActionListener
public class Craps extends JApplet implements ActionListener
^
1 error

Process completed.

[sha256cn]

这是因为你定义的类Craps没有实现他的接口ActionListener的一个方法actionPerformed

[loveyousomuch]

public void actionperformed(ActionEvent e)
{
play();
}
这句话有误，函数名写错了！！actionPerformed

[Mars_wx]

public void actionperformed(ActionEvent e)
{
play();
}

应该是
public void actionPerformed(ActionEvent e)
{
play();
}

编译器以为你重写了个方法