GUI图形化界面里面提到WindowListener接口有七个抽象方法，而它的子类WindowAdapter却没有一个抽象方法，文档我都看了我想问的是怎样看是不是抽象方法

我一般这样去看。进去源码。去JDK中的src.zip中
/*
* @(#)WindowAdapter.java        1.22 06/04/13
*
* Copyright 2006 Sun Microsystems, Inc. All rights reserved.
* SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
*/

package java.awt.event;

/**
* An abstract adapter class for receiving window events.
* The methods in this class are empty. This class exists as
* convenience for creating listener objects.
* <P>
* Extend this class to create a <code>WindowEvent</code> listener
* and override the methods for the events of interest. (If you implement the
* <code>WindowListener</code> interface, you have to define all of
* the methods in it. This abstract class defines null methods for them
* all, so you can only have to define methods for events you care about.)
* <P>
* Create a listener object using the extended class and then register it with
* a Window using the window's <code>addWindowListener</code>
* method. When the window's status changes by virtue of being opened,
* closed, activated or deactivated, iconified or deiconified,
* the relevant method in the listener
* object is invoked, and the <code>WindowEvent</code> is passed to it.
*
* @see WindowEvent
* @see WindowListener
* @see <a >Tutorial: Writing a Window Listener</a>
*
* @author Carl Quinn
* @author Amy Fowler
* @author David Mendenhall
* @version 1.22, 04/13/06
* @since 1.1
*/
public abstract class WindowAdapter
    implements WindowListener, WindowStateListener, WindowFocusListener
{
    /**
     * Invoked when a window has been opened.
     */
    public void windowOpened(WindowEvent e) {}

    /**
     * Invoked when a window is in the process of being closed.
     * The close operation can be overridden at this point.
     */
    public void windowClosing(WindowEvent e) {}

    /**
     * Invoked when a window has been closed.
     */
    public void windowClosed(WindowEvent e) {}

    /**
     * Invoked when a window is iconified.
     */
    public void windowIconified(WindowEvent e) {}

    /**
     * Invoked when a window is de-iconified.
     */
    public void windowDeiconified(WindowEvent e) {}

    /**
     * Invoked when a window is activated.
     */
    public void windowActivated(WindowEvent e) {}

    /**
     * Invoked when a window is de-activated.
     */
    public void windowDeactivated(WindowEvent e) {}

    /**
     * Invoked when a window state is changed.
     * @since 1.4
     */
    public void windowStateChanged(WindowEvent e) {}

    /**
     * Invoked when the Window is set to be the focused Window, which means
     * that the Window, or one of its subcomponents, will receive keyboard
     * events.
     *
     * @since 1.4
     */
    public void windowGainedFocus(WindowEvent e) {}

    /**
     * Invoked when the Window is no longer the focused Window, which means
     * that keyboard events will no longer be delivered to the Window or any of
     * its subcomponents.
     *
     * @since 1.4
     */
    public void windowLostFocus(WindowEvent e) {}
}

这是它的全部信息，一般有什么问题直接去源码里找，问题解决的比较透彻