How to use an object of type class from an generic class as a parameter? - generics and reflection combined

I have two classes:

public abstract class MyAbstractSuperClass<A, B> {

    public MyAbstractSuperClass(Class<A> a, Class<B> b) {
        ...
    }

    ...
}

public class MyClass<A> extends MyAbstractSuperClass<A, MyOtherClass<A>> {

    public MyClass(Class<A> a) {
    super(a, MyOtherClass.class));
            ...
    }

    ...
}

Now you see, the subclass has to call the superclas开发者_Python百科s's constructor. At that line I get the following error:

The constructor MySuperClass<A, MyOtherClass<A>>(Class<A>, Class<MyOtherClass>) is undefined

• So how do I get an object of type Class<MyOtherClass<A>>?
• And how do I do it in the super constructor call, where I can't execute much?

Thanks in advance.

---

The constructor is expecting a Class<MyOtherClass<A>>, not a Class<MyOtherClass>. The only way I can think to satisfy the compiler is through an ugly series of casts:

@SuppressWarnings("unchecked") 
public MyClass(Class<A> a) {
   super(a, (Class<MyOtherClass<A>>)(Class<?>)MyOtherClass.class);
}

It is type safe as seen through inspection, since the class literal for the raw type MyOtherClass is the same as for the parameterized MyOtherClass<A>. But that doesn't stop an unchecked warning from being generated, which can be suppressed as above, or simply ignored.

---

Remove the type parameter of MyOtherClass in the MyClass definition. You're apparently not interested in this anywhere in MyClass' body.

public class MyClass<A> extends MyAbstractSuperClass<A, MyOtherClass> {
    public MyClass(Class<A> a) {
       super(a, MyOtherClass.class);
    }
}

Add a @SuppressWarnings("rawtypes") if the warning bothers you.

---

You must add a second argument to the MyClass constructor:

public MyClass(Class<A> a, Class<MyOtherClass<A>> bClass) {
    super(a, bclass));
}

@Bert F: This does "pass the buck" in some sense, but it passes the buck to someone who can actually provide a class literal of the appropriate type. The caller knows the actual value of the type variable A, and so can provide a class literal of the correct type. Due to erasure, MyClass can't do that.