Java泛型void / Void类型 [英] Java generics void/Void types

问题描述

我正在为apache HttpClient包实现 ResponseHandler ，如下所示：

I am implementing a ResponseHandler for the apache HttpClient package, like so:

new ResponseHandler<int>() {
    public int handleResponse(...) {
        // ... code ...
        return 0;
    }
}

但我想要 handleResponse 函数不返回任何内容，即 void 。这可能吗？以下内容无法编译，因为 void 不是有效的Java类型：

but I'd like for the handleResponse function to return nothing, i.e. void. Is this possible? The following does not compile, since void is not a valid Java type:

new ResponseHandler<void>() {
        public void handleResponse(...) {
            // ... code ...
        }
}

我想我可以用 void > Void 返回 Void 对象，但这不是我想要的。 问题：是否可以组织此回调情况，以便从 handleResponse void c $ c>？

I suppose I could replace void with Void to return a Void object, but that's not really what I want. Question: is it possible to organize this callback situation in such a way that I can return void from handleResponse?

推荐答案

泛型只处理对象类。泛型不支持void和原始类型，您不能将它们用作参数化类型。你必须使用Void。

Generics only handles object classes. void and primitive types are not supported by Generics and you cannot use these as a parameterized type. You have to use Void instead.

你能说出为什么你不想使用 Void ？

Can you say why you don't want to use Void?

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