Spring Boot Testing Spring Applications 5

Question 1

Which Spring Boot feature allows you to override property values specifically for a test class?

Accepted Answer

@TestPropertySource

Answer

@TestPropertySource lets you specify properties files or inline key-value pairs that override application properties during a specific test.

Question 2

What is the purpose of using WireMock in Spring Boot integration tests?

Accepted Answer

To stub and verify HTTP calls to external services without hitting real endpoints

Answer

WireMock starts a local HTTP stub server that you can configure to return predefined responses, isolating your app from real external HTTP dependencies.

Question 3

What does the @AutoConfigureMockMvc annotation do when used alongside @SpringBootTest?

Accepted Answer

Enables MockMvc auto-configuration so it can be injected without @WebMvcTest

Answer

@AutoConfigureMockMvc tells Spring Boot to configure and inject a MockMvc instance even when using the full @SpringBootTest context.

Question 4

In a Testcontainers-based Spring Boot test, what is the typical use of @DynamicPropertySource?

Accepted Answer

To override Spring properties at runtime with values from a started container (e.g., JDBC URL)

Answer

@DynamicPropertySource lets you register container-specific properties (like the JDBC URL from a PostgreSQL container) into the Spring Environment before the context loads.

Question 5

How can you assert that a Spring component throws a specific exception using JUnit 5?

Accepted Answer

Both B and C achieve the goal but B is preferred

Answer

assertThrows() is the idiomatic JUnit 5 approach and returns the exception for further assertions, but a try-catch also works technically.

Spring Boot Practice Test

Spring Boot Practice Test

Spring Boot Testing Spring Applications 5