Spring Boot Mockito Support

External

• https://www.baeldung.com/injecting-mocks-in-spring
• https://spring.io/blog/2016/04/15/testing-improvements-in-spring-boot-1-4#mocking-and-spying

Internal

• Spring Boot Testing Concepts

Overview

Spring Boot has built-in Mockito support and no additional dependencies are required in the Gradle build.gradle file to use Mockito mocks. This article describes the minimal amount of steps to use Mockito mocks in tests, alongside whatever components and real JPA repositories the application uses. Note that a H2-based JPA repository is better than a Mockito mock.

@MockBean

Mocks will be automatically reset across tests.

Dependencies

dependencies {
  ...
  testImplementation 'org.springframework.boot:spring-boot-starter-test'
  testImplementation 'org.mockito:mockito-core:3.12.4'
}

Example

@RunWith(SpringRunner.class)
@SpringBootTest
public class SomeTest {

    @Autowired
    private TestRestTemplate restTemplate;

    @MockBean
    private SomeService someService;

    @Before
    public void setup() {

        // this stubs behavior
        given(someService.getSomething("blah")).willReturn(new Something("blah"));
    }

    @Test
    public void test() {

        restTemplate.getForEntity("/{username}/something, String.class, "blue");
    }
}