M04 Q38 When do you want to use @SpringBootTest annotation?

You should use @SpringBootTest annotation whenever writing JUnit Integration Test for product that is using Spring Boot.

Spring Boot approach to Integration Testing simplifies it by eliminating requirement of application deployment or establishing connection to other infrastructure.

@SpringBootTest annotation enables Spring Boot specific features on top of Spring Test that are useful for testing, like:

• Automated Context creation through SpringApplication class
• Web Environment for Testing – Mocked or Embedded
• Mocked Bean Injection via @MockBean annotation
• Spy Injection via @SpyBean annotation
• Ability to customize created context with @TestConfiguration annotated classes
• Auto configurations for: MVC Testing, JSON Testing, JPA Tests, JDBC Tests, Mongo Db Tests, and much more...

To use @SpringBootTest annotation, you will need to add @RunWith(SpringRunner.class) annotation on top of your test class first, this is required only for JUnit 4, for JUnit 5 @ExtendWith(SpringExtension.class) annotation is already contained in @SpringBootTest annotation.

Next you need to use @SpringBootTest annotation: