What is the difference between <T> T and T in java?

Question

Why is an error reported? Isn’t first the T type? And <T> What is the difference between T and T?

Answer 1

If you wish getMax 方法的返回值类型为 T，就要这样去定义getMaxMethod:

public T getMax()

If you want the type of return value of the getMax method to be determined by the caller, then define the getMax method like this:

public <A> A getMax() {
    //...
    return (A)result;
}

The A here must not be the same letter as the T declared in the class name.

In short, the T and <T> T you mentioned are fundamentally two different uses.

Answer 2

You should remove the second <T>.
<T> is to define generics and T is to use generics
You need to understand generic classes and generic methods

The <T> on the reason class and the <T> on the method should not appear repeatedly, otherwise it will be considered that the generic type has been redefined on the method.