参考“这个”而调用超级构造函数？

问题描述

我有一个类A，写一个子类B.一个只有一个参数化的构造函数。 B必须调用这个超级构造函数A.
现在我想使用一个Object作为参数。这个对象应该调用B的方法。因此，parameter-object必须保存B的引用或必须是一个内部类。

  public B（）{
 super。（new parameter（this））
} 
 
 
 
 
现在当我想调用构造函数时... Eclipse说：
我看到的唯一的事情是解决这个问题，是一个set方法，注入this实例到参数对象。我不想编辑超类。
 
 
 
你看到更好的方法。
解决方案
编译器真的阻止你在这里脚下射击自己。 B不是完全构造，直到调用超级构造函数，所以如果你传递这（如果编译器允许它）作为参考，并且它调用B上的方法，B将处于无效状态，并导致各种（实际上，A仍然没有初始化，也没有任何类的链，包括Object）。
 
 
 
显而易见的解决方案是提供B外的功能并将其传递给参数的构造函数。具体的解决方案将取决于具体的问题，但是B内部的静态嵌套类（由于同样的原因它需要是静态的 - 一个内部类有一个对外部类实例的隐式引用）可能提供该功能。也许你需要重新思考参数B和它的超类之间的关系。这一切都取决于情况。 
 
I have a class A and write a subclass B. A has only one constructor which is parameterised. B has to call this super constructor of A.
Now I want to use an Object as a parameter. This object should call a method of B. So the parameter-object has to hold a reference of B or has to be an inner class. 
public B(){
   super.(new parameter(this))
}
Now when I want to invoke the constructor like... Eclipse says:
The only thing I see to get around this, is a set-method, to inject the "this"-instance into the parameter object. I would not like to edit the super-class.
Do you see any better way around this.
 解决方案 
The compiler is really preventing you from shooting yourself in the foot here. B isn't fully constructed until after the call to the super constructor, so if you pass this (if the compiler allowed it) as a reference, and it calls a method on B, B would be in an invalid state and cause all kinds of nasty problems (in fact, A is still not initialized, nor any class up the chain, including Object).
The obvious solution is to provide the functionality outside of B and pass that to the constructor of the parameter. Specific solutions will depend on the specific problem, but a static nested class inside B (it needs to be static for the same reason - an inner class has an implicit reference to the outer class instance) could provide that functionality, perhaps. Maybe you need to rethink the relationship between the parameter, B and its super class. It all depends on the case. 
                        
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