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请问java中this的这种用法？DnDExample.this.dispose()

摘要: 请问java中this的这种用法？DnDExample.this.dispose()

/*
* Copyright (C) 1996-2002 by ILOG.
* All rights reserved.
*
* This source code is an addition to the ILOG JViews Reference Manual
* delivered with the JViews library.
* It is supplied as an example to show you how to code with JViews.
* Feel free to use, copy or modify it within the framework of your
* JViews license agreement.
*/
/*
* $Id: DnDExample.java,v 1.10 2002/10/17 15:47:41 laudazzi Exp $
*/

package dnd;

import ilog.views.*;
import ilog.views.swing.*;
import java.awt.*;
import java.awt.event.*;
import java.awt.dnd.*;
import java.awt.datatransfer.*;
import javax.swing.*;
import java.util.ArrayList;

/*
* This example launches a JFrame containing two JInternalFrame. You can drag and drop
* IlvGraphic from one frame to another.
*/
public class DnDExample extends JFrame {
private IlvManager mg1;
private IlvManager mg2;
private boolean main = false;
private static ArrayList desktops = new ArrayList();

public static void main(String[] arg) {
new DnDExample();
}

public DnDExample() {
super("Drag'n'Drop Sample");
setSize(800, 685);
addWindowListener(new WindowAdapter() {
public void windowClosing(WindowEvent e) {
DnDExample.this.dispose();//这里的this
desktops.remove(DnDExample.this);
if (desktops.size() == 0 || main)
System.exit(0);
}
});
}
}
请问，这里的this 是什么用法？我查了dispose() 是java.awt.Window类下的方法。因为这里的this是在匿名类里调用的，所以要这么用DnDExample.this来调用匿名类外部的方法dispose()。这里的DnDExample.this是指的DnDExample类的实例吧？但是怎么和java.awt.Window类扯上关系了呢？不知道是怎么回事？还是我理解的有问题？

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内部类调用外部类方法时要使用 “外部类名.this.方法名();”

DnDExample.this指的是DnDExample类，而DnDExample继承的是JFrame（javax.swing.JFrame）

继承关系如下

java.lang.Object
－java.awt.Component
－java.awt.Container
－java.awt.Window
－java.awt.Frame
－javax.swing.JFrame

所以JFrame也有dispose()方法啊。

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DnDExample继承了JFrame,JFrame继承了java.awt.Window，因此。。。。
就这么简单

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因为DnDExample继承自JFrame，而javax.swing.JFrame又继承自java.awt.Frame，同样
java.awt.Frame继承自java.awt.Window
类层次：
java.awt.Window
java.awt.Frame
javax.swing.JFrame
DnDExample
查看下API文档就清楚的事情

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JFrame从java.awt.Window继承来了dispose()方法，你的理解没错

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晕了，太不细心了。没看到Frame extends Window.
thx all together!

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