Type arguments in Java

Question

Is there any difference between the following two declarations?

public> List search (C condition)

public List

        

Answer 1

No, there's no useful difference. The distinction could be simplified to the following.

 void m(T object)

void m(Object object)

Although with the first one could call this.m(42) and it wouldn't compile - but there's no value to that.

The value of a generic method comes when there is some relationship expressed by its type parameters, for example:

 T giveItBackToMe(T object) {
    return object;
}

...

String s = giveItBackToMe("asdf");
Integer i = giveItBackToMe(42);

Or:

 void listCopy(List from, List to) {
    to.addAll(from);
}

...

List ints = Arrays.asList(1, 2, 3);
List nums = new ArrayList<>();
listCopy(ints, nums);