Java - Inheriting from a class that accepts generics? [closed]

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How do you inherit from this class? The following code is broken but it shows what I'm trying to achieve.

Bound Mismatch: The type T is not a valid substitude for the bounded parameter of the type ActivityInstrumentationTestCase2

public class MyClass<T> extends ActivityInstrumentationTestCase2<T> {
     public MyClass (Class<T> cl开发者_如何学Goazz) {
          super(clazz);
     }
}

---

What is the class definition of ActivityInstrumentationTestCase2?

Most likely, ActivityInstrumentationTestCase2 is defined as:

class ActivityInstrumentationTestCase2<T extends SomeObject> {
 ...
}

In which case, your object's parameters needs to stay within its superclass's parameters.

For example:

public class MyObject<T extends SomeObject> extends ActivityInstrumentationTestCase2<T> {
...
}

You could also make the parameter narrower. So, if MySomeObject extended SomeObject you could also say:

public class MyObject<T extends MySomeObject> extends ActivityInstrumentationTestCase2<T> {
...
}

Edit to add: I just found this. I assume you're using the same one, so it needs to be defined as:

public class MyObject<T extends android.app.Activity> extends ActivityInstrumentationTestCase2<T> {
...
}