Question

I have an interface like so:

public interface MyInterface<E extends Something1> {
    public void meth1(MyClass1<E> x);
}

and I have a subclass whose superclass implements the above interface:

public class MyClass2<E extends Something1> extends Superclass{

    public MyClass2(){

    }

    public void meth1(MyClass1 x) {
        // TODO Auto-generated method stub

    }
}

superclass:

public abstract class Superclass<E extends Something1> implements MyInterface{
    MyClass1<E> x;
    protected E y;

    public Superclass(){

    }
}

MyClass1:

public abstract class Myclass1<E extends Something1> {

    public Myclass1(){

    }
}

the problem is that the parameter for meth1() is supposed to be generic. If I do MyClass1 it doesn’t like it and the only way I can get it to compile is by leaving out generic parameters- which feels wrong.

What’s going wrong?

Answer 1

Here are your classes now parameterised appropriately:

class Something1 { }

public interface MyInterface<E extends Something1> {
    public void meth1(MyClass1<E> x);
}

// and I have a subclass whose superclass implements the above interface:
public class MyClass2<E extends Something1>
    extends Superclass<E> {

    public MyClass2() { }

    public void meth1(MyClass1<E> x) { }
}

// superclass:
public abstract class Superclass<E extends Something1> implements
        MyInterface<E> {
    MyClass1<E> x;
    protected E y;

    public Superclass() { }
}

// MyClass1:
public abstract class MyClass1<E extends Something1> {

    public MyClass1() {

    }
}