Mockito IMHO you need to add a @RunWith (some.mockito.TestSuiteIDontRememberName.class) annotated to the test class. This version of whenAddCalledVerified () accomplishes the same thing as the one above: We'll cover doAnswer () below. And what I knew was the code enters to throwable after getting Null Pointer Exception on … @Mock. MockitoAnnotations (Mockito 2.2.28 API) java.lang.Object. Let's test the MathApplication class, by injecting in it a mock of calculatorService. Null pointer exception when using Mockito to mock interface They both achieve the same result. However, In JUnit 5, the annotation @ExtendWith is repeatable, so you can use it without worrying about the exclusivity.. After each test case, Mockito extension validates the framework state to detect … The @Mock annotation requires a test suite that searches for the annotation and gathers the information to inject the values there. I use the powermockito mock a final class .but the mock object is the null .I can't find out the … In the following example, we'll create a mocked ArrayList manually without using the @Mock annotation: As per Mockito you can create mock object by either using @Mock or Mockito.mock(Context.class);, We can specify the mock objects to be injected using @Mock or @Spy annotations. This article is a short list of 3 most common reasons why this might be happening. Mockito mock java method class NullPointerException Connect and share knowledge within a single location that is structured and easy to search. Annotation Magic with Mockito: InjectMocks - Encora Also you can simplify your test code a lot if you use @InjectMocks annotation. Mockito To ensure the exception message thrown from an unsuccessful verification includes the provided name of a mock, we'll rely on a JUnit implementation of the TestRule interface, ExpectedException, and include it in a test class: You are trying to mock two methods at once. Mockito’s @InjectMocks annotation usually allows us to inject mocked dependencies in the annotated class mocked object. In this line: Mockito.when (valueProducerFactory.createValueProducer ("IdProducer", Collections.emptyList ()).get ()).thenReturn (mappedValue); you are calling get () on the result of the createValueProducer () call, which is null because you haven't mocked it yet. The Mockito framework allows us to create mock objects using either @Mock annotation or mock() static method.