如何在java中包装泛型类

如果我正在为泛型类编写一个包装器,我已经尝试将类型嵌入at构造(如 this SO question ):

class Foo<T> {
    private T value;
    private Class<T> type;

    public Foo(Class<T> type, T value) {
        this.value = value;
        this.type = type;
    }

    public T getValue() {
        return value;
    }

    public Class<T> getType() {
        return type;
    }
}

Foo ,我想将其转换为 FooWrapper

List<Foo<?>> someListOfFoos = ...
List<FooWrapper<?>> fooWrappers = someListOfFoos
    .stream()
    .map(foo -> FooWrapper.from(foo))
    .collect(Collectors.toList());

有没有办法恢复中每个元素的类型 someListOfFoos 在构建每个 食品包装机 ? 大致如下:

class FooWrapper<T> {
    private Foo<T> foo;

    public static FooWrapper<?> from(Foo<?> toWrap) {
        Class<E> type = toWrap.getType(); // i know this is wrong
        return new FooWrapper<type>(toWrap); // this is very wrong
    }

    private FooWrapper(Foo<T> foo) {
        this.foo = foo;
    }
}