如何强制对super方法进行多态调用？ [英] How do I force a polymorphic call to the super method?

问题描述

我有一个init方法，通过广泛的层次结构使用和覆盖。然而，每个init调用都扩展了之前的工作。很自然地，我会：

I have an init method that is used and overridden through out an extensive heirarchy. Each init call however extends on the work that the previous did. So naturally, I would:

@Override public void init() {
   super.init();
}

当然，这将确保调用和实例化所有内容。我想知道的是：我可以创建一种方法来确保调用super方法吗？如果所有的init都没有调用，那么obejct就会出现故障，所以如果有人忘记调用 super ，我想抛出异常或错误。

And naturally this would ensure that everything is called and instantiated. What I'm wondering is: Can I create a way to ensure that the super method was called? If all of the init's are not call, there is a break down in the obejct, so I want to throw an exception or an error if somebody forgets to call super.

TYFT~Aedon

TYFT ~Aedon

推荐答案

以下是提出异常的一种方法派生类无法调用超类：

Here's one way to raise an exception if a derived class fails to call up to the superclass:

public class Base {
    private boolean called;
    public Base() { // doesn't have to be the c'tor; works elsewhere as well
        called = false;
        init();
        if (!called) {
            // throw an exception
        }
    }
    protected void init() {
        called = true;
        // other stuff
    }
}

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