My team is migrating an enterprise app and ran into a circular reference error during startup. How does dependency injection in Spring Boot handle circular dependencies, and what is the cleanest architectural way to refactor this code?
3 answers
Is setting spring.main.allow-circular-references=true in application properties a viable long-term solution for large enterprise legacy software development?
The @Lazy annotation is great for quick fixes, but architectural refactoring should always be your main priority to keep components modular.
I agree completely with Cynthia. Circular dependencies are almost always a symptom of tightly coupled classes that are trying to do way too much. Break them apart early.
Circular dependencies happen when Bean A requires Bean B, and Bean B requires Bean A. In modern versions, dependency injection in Spring Boot disables circular references by default, causing a startup crash. The cleanest way to fix this is to refactor your code by introducing a third bean to hold the shared logic, or by using interfaces to break the direct cycle. As a temporary workaround, you can use the @Lazy annotation on one of the injection points so the bean is instantiated only when needed.
Absolutely not, Raymond. Turning that flag on is a technical debt trap. It masks deep architectural flaws and can lead to unexpected runtime issues and difficult debugging scenarios as your codebase continues to expand.