package drawline;import java.awt.*;import javax.swing.JPanel;import java.awt.event.*;/** * Title: * Description: * Copyright:    Copyright (c) 2001 * Company: * @author * @version 1.0 */public class MyPanel extends JPanel {  BorderLayout borderLayout1 = new BorderLayout();  Label label1 = new Label();  Point p = null;  Panel panel1 = new Panel();  Button button1 = new Button();  Button button2 = new Button();  public MyPanel() {    try {      jbInit();    }    catch(Exception ex) {      ex.printStackTrace();    }  }  void jbInit() throws Exception {    this.addMouseMotionListener(new java.awt.event.MouseMotionAdapter() {      public void mouseMoved(MouseEvent e) {        this_mouseMoved(e);      }    });    this.setLayout(borderLayout1);    this.addMouseListener(new java.awt.event.MouseAdapter() {      public void mouseClicked(MouseEvent e) {        this_mouseClicked(e);      }    });    button1.setLabel("New Line");    button1.addActionListener(new java.awt.event.ActionListener() {      public void actionPerformed(ActionEvent e) {        button1_actionPerformed(e);      }    });    button2.setLabel("Clear All");    button2.addActionListener(new java.awt.event.ActionListener() {      public void actionPerformed(ActionEvent e) {        button2_actionPerformed(e);      }    });    this.add(label1, BorderLayout.SOUTH);    this.add(panel1, BorderLayout.NORTH);    panel1.add(button1, null);    panel1.add(button2, null);  }/*  public void paintComponent(Graphics g){    super.paintComponent(g);    //g.setColor(Color.red);    //g.drawLine(1,1,23,20);    //g.drawLine(10,10,90,90);  }*/  void this_mouseMoved(MouseEvent e) {    String s = "("+String.valueOf(e.getX())+","+String.valueOf(e.getY())+")";    if (p != null)      s = "Line To:" + s;    label1.setText(s);  }  void this_mouseClicked(MouseEvent e) {    Graphics g = this.getGraphics();    g.setColor(Color.red);    if (p != null)      g.drawLine(e.getX(),e.getY(),(int)p.getX(),(int)p.getY());    p = new Point(e.getX(),e.getY());  }  void button2_actionPerformed(ActionEvent e) {    Graphics g = this.getGraphics();    g.clearRect(0,0,this.getWidth(),this.getHeight());    p = null;  }  void button1_actionPerformed(ActionEvent e) {    p = null;  }}