Java通用字段声明 [英] Java generic field declaration

问题描述

在没有泛型类型的类中，我想声明一个类似于这些的相当复杂的泛型字段：

In a class without generic types I want to declare a rather complex generic field similar to these:

public class Client {
    private Map<Class<T extends Serializable>, List<Consumer<S extends T>>> classToConsumerTry1;

    private <T extends Serializable, S extends T> Map<Class<T>, List<Consumer<S>>> classToConsumerTry2;
}

promblem是java编译器不会让我：）

promblem is the java compiler won't let me :)

所以我的问题是如何正确引入T和S而不向我的班级客户添加类型。

So my question is how do I correctly introduce T and S without adding types to my class Client.

我的目标是强制执行 Class 作为 Serializable 的子类型和 Consumer 是您为 Class 选择的类的子类型。

My goal is to enforce the Class being a subtype of Serializable and the Consumer being a subtype of the class you chose for Class.

推荐答案

你不能。您唯一的选择是在 Client 类声明中声明泛型类型参数。如果 Client 类没有泛型类型参数，则其成员不能是通用的。您必须在班级成员的声明中使用实际类型。

You can't. Your only option is to declare the generic type parameters in your Client class declaration. If your Client class has no generic type parameters, its members can't be generic. You must use actual types in the declaration of your class members.

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