这个代码哪位大神可以帮忙改一下。。

Question

import java.awt.*;

import java.awt.event.*;

import javax.swing.*;

public class HelloWorld3 {

public static void main(String[] args){

JFrame frame = new JFrame(" HelloWorld3 ");

frame.add(new HelloComponent3("Hellow"));

frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

frame.setSize(300,300);

frame.setVisible(true);

}

}

class HelloComponent3 extends JComponent

  implements MouseMotionListener,ActionListener

  {

String theMessage;

int messageX=125,messageY=95;

JButton theButton;

int colorIndex;

static Color[] someColors={Color.black,Color.red,Color.green,Color.blue,Color.magenta};

public HelloComponent3(String message){

theMessage=message;

theButton=new JButton("change message");

setLayout(new FlowLayout());

add(theButton);

theButton.addActionListener(this);

addMouseMotionListener(this);

}

public void painComponent(Graphics g){

g.drawString(theMessage, messageX, messageY);

}

public void mouseDragged(MouseEvent e){

messageX=e.getX();

messageY=e.getY();

repaint();

}

public void mouseMoved(MouseEvent e){}

    public void actionperformed(ActionEvent e){

    if(e.getSource()== theButton)

    changeColor();

    }

    

    synchronized private void changeColor(){

    if(++colorIndex==someColors.length)

    colorIndex=0;

    setForeground(currentColor());

    repaint();

    }

    

    synchronized private Color currentColor(){

    return someColors[colorIndex];

    }

public void actionPerformed(ActionEvent e) {

}

  }