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

public class TestApplet {
public static void main(String[] args) {
DrawFrame frame=new DrawFrame();
frame.setVisible(true); //不要用show方法了。該方法過時了，被setVisitble(Boolean b)方法取代了。
}
}

class DrawFrame extends Frame {

private static final long serialVersionUID = 1L;

public DrawFrame() {
setTitle("DrawTest");
setSize(500,400);
DrawPanel panel=new DrawPanel();
add(panel);
this.addWindowListener(new WindowAdapter(){
public void windowClosing(WindowEvent evt){
System.exit(0);
}
});
}
}

class DrawPanel extends Panel{
/**
*
*/
private static final long serialVersionUID = 1L;

private int x,y;

public DrawPanel() {

this.addMouseListener(new MouseAdapter(){

public void mousePressed(MouseEvent evt) {
x=evt.getX();
y=evt.getY();
}

public void mouseReleased(MouseEvent evt) {
Graphics m=getGraphics();
m.drawLine(x, y, evt.getX(), evt.getY());
}
});
}
}