[Solved] What is wrong with this Spring Boot IoC setup?@Component public class Controller { private Service service; public void setService(Service service) { this.service = service; } } | Spring Boot

Spring Boot - Inversion of Control and Dependency Injection

What is wrong with this Spring Boot IoC setup?

@Component
public class Controller {
  private Service service;

  public void setService(Service service) {
    this.service = service;
  }
}

AService class must be final

BController class must have a constructor with Service parameter

CSetter injection is missing @Autowired annotation

DNo @Component annotation on Service class

Step-by-Step Solution

Solution:

Step 1: Identify injection method used
Setter injection is used but lacks @Autowired to tell Spring to inject.
Step 2: Understand Spring injection requirements
Setter methods must be annotated with @Autowired for Spring to inject dependencies.
Final Answer:
Setter injection is missing @Autowired annotation -> Option C
Quick Check:
Missing @Autowired on setter = No injection [OK]

Quick Trick: Annotate setters with @Autowired for injection [OK]

Common Mistakes:

Master "Inversion of Control and Dependency Injection" in Spring Boot

9 interactive learning modes - each teaches the same concept differently

More Spring Boot Quizzes

What is wrong with this Spring Boot IoC setup?