Spring Boot Externalized Configuration and Profiles 5

Question 1

What is the effect of adding @Profile("!prod") to a @Bean method?

Accepted Answer

The bean is created in all profiles except production

Answer

The ! operator in @Profile expressions negates the condition, so !prod means the bean loads when the prod profile is NOT active.

Question 2

Which property overrides the default config file location in Spring Boot?

Accepted Answer

spring.config.location

Answer

spring.config.location replaces the default search paths entirely with the specified locations.

Question 3

How does Spring Boot handle a @ConfigurationProperties class with a nested object field?

Accepted Answer

Nested objects are bound automatically using dot-separated property names

Answer

Spring Boot recursively binds nested POJO fields using dot notation, e.g., app.database.host maps to a nested object's host field.

Question 4

What Spring Boot feature allows overriding properties per-test without modifying application.properties?

Accepted Answer

@TestPropertySource

Answer

@TestPropertySource allows specifying properties or property files that override the application's default configuration during tests.

Question 5

Which bean validation annotation ensures a @ConfigurationProperties field is not null at startup?

Accepted Answer

@NotNull

Answer

@NotNull from javax.validation triggers a startup failure if the bound property is missing or null, when validation is enabled.

Spring Boot Practice Test