使用Java泛型确保类型安全

Question

I am trying to improve the type safety of the following method:

A<String> method(B<String> arg);

How do I make sure that this method is not called with a raw type B and that compiler always checks for String type specified?

Answer 1

You can't prevent someone from calling a method with a raw type.

The reason is for backward compatibility with pre-generic versions of java.

Answer 2

If the compiler warnings are turned on ( -Xlint:unchecked ), you will get a warning if that method is called with a raw type:

warning: [unchecked] unchecked conversion A a = method(new B());