When calling abstract method from concrete class throwing NullPointerException

Question

I am testing a method in a class. Which is calling a method of abstract class.

Eg:

class abstract Abstract {
  public ReturnObject abstractMethod(SomeObject value) {
    // do something
    return returnObject;
  }
}

class Concreate extends Abstract {
   public ReturnObject concreteMethod(SomeObject value) {
   //do something
   returnObject = abstractMethod(value);
   return returnObject;
   }

}

My UT is 

class ConcreateTest {
  @InjectMocks
  private Concreate conctrete;

  @Mock
  private Concreate conctrete2;

  @Test
  public void test_method() {
     when(conctrete2.abstractMethod(value)).thenReturn(returnObject);
     conctrete.concreteMethod(value);
  }

}

This way it is returning me NullPointerException.

You didn't add minimal code that could be compiled? seeing your code we can't help you out, and add error trace too. to get quick solution. — smali, May 13 '16 at 04:20
@FaizAli Sorry I rejected your edit by mistake thinking that you are removing the spaces, I apologize For that. But it will be approved, not to worry. — Shree Krishna, May 13 '16 at 04:30

score 0 · Answer 1 · answered May 13 '16 at 04:25

From what you are showing, I see very little of your code to tell for sure what's going on, but one thing I see is that you are mocking one Concreate and then injecting that mock into another Concreate. I don't see in the code you are showing anywhere that tells me that a Concreate uses another injected Concreate. This essentially is just pseudo-code. So essentially I am assuming that your main Concreate is being injected in an application context and that your other Concreate is being injected in the first one.

You need @Named to solve this ambiguity or more generically speaking you must give your beans an individual name, even if they are mocked.

When calling abstract method from concrete class throwing NullPointerException

1 Answers1