“这个”施工期间参考逃逸？ [英] "this" reference escaping during construction?

问题描述

如果我执行以下操作，

  final class FooButton extends JButton {
 FooButton（）{
 super（Foo）; 
 addActionListener（new ActionListener（）{
 @Override 
 public void actionPerformed（ActionEvent e）{
 // do stuff 
} 
} 
} 
} 
  

是的，因为在匿名内部类中，你可以像这样访问它。 ：

  final class FooButton extends JButton {
 Foo（）{
 super（Foo）; 
 addActionListener（new ActionListener（）{
 @Override 
 public void actionPerformed（ActionEvent e）{
 FooButton button = FooButton.this; 
 // ... do有按钮的东西
} 
}）; 
} 
} 
  

匿名在 FooButton 对象完全初始化之前，原则上可以调用ActionListener 并使用 FooButton 。

If I do the following,

final class FooButton extends JButton{
    FooButton(){
        super("Foo");
        addActionListener(new ActionListener(){
            @Override
            public void actionPerformed(ActionEvent e){
                // do stuff
            }
        });
    }
}

am I letting the this reference implicitly escape?

解决方案

Yes, because in the anonymous inner class you could access it like this:

final class FooButton extends JButton {
    Foo() {
        super("Foo");
        addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                FooButton button = FooButton.this;
                // ... do something with the button
            }
        });
    }
}

The code of the anonymous ActionListener could in principle be called and use the FooButton before the FooButton object is fully initialized.

这篇关于“这个”施工期间参考逃逸？的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！