现在在国外大学里最流行的java学习软件,同时还有大量的example,在名为project的文件里.安装好后用bluej打开peoject的例子,可以进行你想要的任何变化.同时可以了解大量的源码

				/**				 * The main class of a simple calculator. Create one of these and you'll				 * get the calculator on screen.				 * 				 * @author David J. Barnes and Michael Kolling				 * @version 2006.03.30				 */				public class Calculator				{				    private CalcEngine engine;				    private UserInterface gui;								    /**				     * Create a new calculator and show it.				     */				    public Calculator()				    {				        engine = new CalcEngine();				        gui = new UserInterface(engine);				    }								    /**				     * In case the window was closed, show it again.				     */				    public void show()				    {				        gui.setVisible(true);				    }				}