import java.awt.*;
import javax.swing.*;
import java.awt.event.*;
import java.util.ArrayList;

/*
<applet archive="MouseDraw.jar" code="MouseDraw.class" width="150" height="150"> </applet>
*/
public class MouseDraw extends JApplet implements MouseListener {
  ArrayList<int[]> points;
  
  @Override
  public void init() {
    points = new ArrayList<>();
    addMouseListener(this);
  }

  public void mouseClicked(MouseEvent e) {
    points.add(new int[] { e.getX(), e.getY() });
    repaint();
  }

  public void mouseEntered(MouseEvent e) {}
  public void mouseExited(MouseEvent e) {}
  public void mousePressed(MouseEvent e) {}
  public void mouseReleased(MouseEvent e) {}

  @Override
  public void paint(Graphics g) {
    super.paint(g);
    
    int i, n = points.size();
    for (i = 1; i < n; i++) {
      int[] p0 = points.get(i - 1);
      int[] p1 = points.get(i);
      g.drawLine(p0[0], p0[1], p1[0], p1[1]);
    }
  }

  public static void main(String[] args) {
    JFrame frame = new JFrame("");
    JApplet applet = new MouseDraw();
    applet.setPreferredSize(new Dimension(150, 150));
    frame.add(applet);
    frame.pack();
    frame.setVisible(true);
    applet.init();
    applet.start();
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
  }

}