@InjectMocks annotation in JUnit - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to create a mock object for the dependency.

JUnit

@Mock
private Service [1];

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Aservice

BService

CmockService

DserviceMock

Attempts:

3 left

💡 Hint

Common Mistakes

Using the class name instead of a variable name.

Adding prefixes like 'mock' unnecessarily.

The field name 'service' is used to declare the mock object for the Service class.

2fill in blank

medium

Complete the code to inject mocks into the tested class.

JUnit

@InjectMocks
private [1] controller;

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Aservice

Bcontroller

CService

DController

Attempts:

3 left

💡 Hint

Common Mistakes

Using the variable name instead of the class type.

Confusing the service class with the controller class.

The tested class type is 'Controller', and the variable name is 'controller'.

3fill in blank

hard

Fix the error in the test setup method to initialize mocks.

JUnit

@BeforeEach
void setUp() {
    MockitoAnnotations.[1](this);
}

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AopenMocks

BinitMocks

CmockStatic

Dmock

Attempts:

3 left

💡 Hint

Common Mistakes

Using deprecated initMocks method.

Calling mockStatic instead of initializing instance mocks.

Since Mockito 3.4.0, MockitoAnnotations.openMocks(this) is the recommended way to initialize mocks.

4fill in blank

hard

Fill both blanks to correctly declare and inject mocks for dependencies.

JUnit

@Mock
private [1] repository;

@InjectMocks
private [2] service;

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ARepository

BService

Crepository

Dservice

Attempts:

3 left

💡 Hint

Common Mistakes

Using variable names instead of class types for mocks.

Mixing up the order of mock and injectMocks declarations.

The mock is declared with the class type 'Repository' and injected into the 'Service' class.

5fill in blank

hard

Fill all three blanks to complete the test class setup with mocks and injection.

JUnit

class UserServiceTest {

    @Mock
    private [1] userRepository;

    @InjectMocks
    private [2] userService;

    @BeforeEach
    void init() {
        MockitoAnnotations.[3](this);
    }
}

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AUserRepository

BUserService

CopenMocks

DinitMocks

Attempts:

3 left

💡 Hint

Common Mistakes

Using deprecated initMocks instead of openMocks.

Mixing variable names with class types in annotations.

Mocks are declared with UserRepository, injected into UserService, and initialized with MockitoAnnotations.openMocks(this).