What does it mean for a non generic class to extend a generic class

Question

public class B extends C  {

}

What does this mean? That C needs to extend A? What extra restriction am I putting instead of just saying B ext

Answer 1

In this case, C is a class that can take a generic parameter, and you are giving it a specific type A as the parameter. Then, B extends that specific parameterization of C.

For example, suppose:

class C {
    T example();
}

class B extends C {
}

Then B.example() would return an Integer.