Mocking method from protected abstract method

Here's my problem in detail.

Setup:

• I have class A that has a private member variable of class B.


• A method(method1) in class A calls a non-static method(method2) in class B.


• Class B actually inherits method2 from a protected abstract class C and does not override it.

Problem:

• I'm writing a test for class A.


• In the test I'm mocking the call to method2.

Sample Code:

B b = Mockito.mock(B.class);
A a = new A(b);
Mockito.when(b.method2()).thenReturn(MY_LIST);

• Now when I call method1(which in turn calls method2), I get a
  
  NullPointerException.

Sample Code:

a.method1();

• I'm assuming that this call is completely independent of the implementation of method2 since I'm mocking it. Is that wrong ? If not, what am I doing wrong ?

PS: class C is protected and Class A is in a different package from class B and C.