Spring Boot Core Container and Beans 5

Question 1

Which annotation, when placed on a @Configuration class, imports bean definitions from another @Configuration class?

Accepted Answer

@Import

Answer

@Import allows one @Configuration class to pull in bean definitions from one or more other @Configuration classes.

Question 2

What does the @PostConstruct annotation indicate in a Spring-managed bean?

Accepted Answer

The method runs after all dependencies have been injected

Answer

@PostConstruct marks a method to be executed after dependency injection is complete, serving as an init callback.

Question 3

In Spring, what is an inner bean?

Accepted Answer

A bean defined inline inside another bean's property without a global id

Answer

An inner bean is defined as a local bean inside another bean's configuration and cannot be referenced by other beans.

Question 4

Which of the following correctly describes field injection vs. constructor injection in Spring?

Accepted Answer

Constructor injection makes dependencies mandatory and supports immutability; field injection does not

Answer

Constructor injection enforces required dependencies at object creation and enables immutable (final) fields, which field injection cannot do.

Question 5

What happens if you annotate a @Bean method inside a non-@Configuration class (e.g., a @Component class) in Spring?

Accepted Answer

The @Bean method works but without CGLIB proxying, so inter-bean calls are plain Java calls

Answer

In a lite-mode (non-@Configuration) class, @Bean methods are not CGLIB-proxied, so calling one bean method from another bypasses the container.

Spring Boot Practice Test