/* * Copyright (c) 2000 David Flanagan.  All rights reserved. * This code is from the book Java Examples in a Nutshell, 2nd Edition. * It is provided AS-IS, WITHOUT ANY WARRANTY either expressed or implied. * You may study, use, and modify it for any non-commercial purpose. * You may distribute it non-commercially as long as you retain this notice. * For a commercial use license, or to purchase the book (recommended), * visit http://www.davidflanagan.com/javaexamples2. */package com.davidflanagan.examples.gui;import javax.swing.*;       // For JPanel componentimport java.awt.*;          // For Graphics objectimport java.awt.event.*;    // For Event and Listener objects/** * A simple JPanel subclass that uses event listeners to allow the user * to scribble with the mouse.  Note that scribbles are not saved or redrawn. **/public class ScribblePane1 extends JPanel    implements MouseListener, MouseMotionListener {    protected int last_x, last_y;  // Previous mouse coordinates    public ScribblePane1() {	// This component registers itself as an event listener for	// mouse events and mouse motion events.	this.addMouseListener(this);	this.addMouseMotionListener(this);	// Give the component a preferred size	setPreferredSize(new Dimension(450,200));    }    // A method from the MouseListener interface.  Invoked when the    // user presses a mouse button.    public void mousePressed(MouseEvent e) {	last_x = e.getX();  // remember the coordinates of the click	last_y = e.getY();    }        // A method from the MouseMotionListener interface.  Invoked when the    // user drags the mouse with a button pressed.    public void mouseDragged(MouseEvent e) {	int x = e.getX();    // Get the current mouse position	int y = e.getY();	// Draw a line from the saved coordinates to the current position	this.getGraphics().drawLine(last_x, last_y, x, y);	last_x = x;          // Remember the current position	last_y = y;    }        // The other, unused methods of the MouseListener interface.    public void mouseReleased(MouseEvent e) {}    public void mouseClicked(MouseEvent e) {}    public void mouseEntered(MouseEvent e) {}    public void mouseExited(MouseEvent e) {}        // The other, unused, method of the MouseMotionListener interface.    public void mouseMoved(MouseEvent e) {}}