java - 在 Java 字段中存储类泛型

Question

有什么方法可以将构造时传入的泛型参数类型存储到参数中。我的目标:

class generic<T> {
    Class<T> type;
    public generic() {
        super();
        this.type = //Something that gets class from T
    }
}

我目前正在做的是:

class generic<T> {
    Class<T> type;
    public generic(Class<T> type) {
        super();
        this.type = type;
    }
}

必须两次指定类似乎很愚蠢，但我不确定还能怎么做。我认为这可能通过反射(reflection)成为可能，但我还没有对此进行调查。有没有更直接的方法？如果不是(顺便说一句)为什么会丢失信息？

Answer 1

因为 Java 泛型是用 Type Erasure 实现的

When a generic type is instantiated, the compiler translates those types by a technique called type erasure — a process where the compiler removes all information related to type parameters and type arguments within a class or method. Type erasure enables Java applications that use generics to maintain binary compatibility with Java libraries and applications that were created before generics.