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implementing Custom Annotations and Reflection in Spring Boot 3.0 for Dependency Injection

👀 Views: 20 đŸ’Ŧ Answers: 1 📅 Created: 2025-06-16
spring-boot annotations dependency-injection reflection Java

I'm working on a personal project and I'm building a feature where I'm working on a Spring Boot 3.0 application where I created a custom annotation `@MyService` to mark certain classes for dependency injection. However, when I attempt to retrieve beans using reflection, it seems like my custom annotation isn't being recognized. Here's my annotation definition: ```java import org.springframework.stereotype.Component; import java.lang.annotation.Retention; import java.lang.annotation.RetentionPolicy; import java.lang.annotation.Target; import static java.lang.annotation.ElementType.TYPE; @Target(TYPE) @Retention(RetentionPolicy.RUNTIME) @Component public @interface MyService { } ``` I've annotated a class like this: ```java @MyService public class MyCustomService { public void execute() { System.out.println("Executing MyCustomService"); } } ``` In my configuration class, I'm trying to scan for these beans: ```java import org.springframework.context.annotation.ComponentScan; import org.springframework.context.annotation.Configuration; @Configuration @ComponentScan(basePackages = "com.example.services") public class AppConfig { } ``` However, when I run the application, I get the following behavior: ``` java.lang.IllegalArgumentException: No qualifying bean of type 'com.example.services.MyCustomService' available ``` I've tried adding `@EnableAspectJAutoProxy` in case there's any proxying happening but that didn't resolve the scenario. I also attempted to use `@Component` directly on my class, which works fine, but I want to stick with my custom annotation for clarity and maintainability. I verified the package structure, and everything seems correct. Am I missing something in the way I'm using annotations or reflection in Spring Boot 3.0? Any insights would be appreciated. For context: I'm using Java on macOS. I'd love to hear your thoughts on this.