👀 Views: 92 💬 Answers: 1 📅 Created: 2025-06-07

spring spring-boot dependency-injection Java

Quick question that's been bugging me - I'm working with an scenario where my Spring Boot application fails to inject a service into the `@PostConstruct` method of my component. I have a component where I want to perform some initialization logic after the bean's properties have been set, which includes using an injected service. However, I'm getting a `NullPointerException` when trying to use the service during the initialization phase. Here is a simplified version of my code: ```java import org.springframework.beans.factory.annotation.Autowired; import org.springframework.stereotype.Component; import javax.annotation.PostConstruct; @Component public class MyComponent { @Autowired private MyService myService; @PostConstruct public void init() { // This line throws NullPointerException myService.performAction(); } } ``` In this case, `MyService` is another Spring component that is supposed to be autowired. I've double-checked that `MyService` is annotated properly with `@Service` and is getting picked up by component scanning. The `@PostConstruct` method is being called after the bean is created, but it seems that the dependency injection hasn't completed yet. I confirmed that this is not the case when I use the service in a regular method of the component where it works fine. I even tried using a `@PreDestroy` method to see if that would work instead, but I still get the same scenario. Is there something specific about using `@Autowired` in `@PostConstruct` that I might be missing, or is there a best practice I should follow to avoid this scenario? Any help would be greatly appreciated! Any ideas what could be causing this?