Resolving the BeanCreationException in Spring Boot: Fixing the LocaleResolver Issue

Learn how to resolve the `BeanCreationException` when working with `LocaleResolver` in your Spring Boot application with this detailed guide.
---

If anything seems off to you, please feel free to write me at vlogize [AT] gmail [DOT] com.
---
Resolving the BeanCreationException in Spring Boot: Fixing the LocaleResolver Issue

Understanding the Problem

In a recent scenario, a developer reported encountering the following error while trying to set up internationalization in a Spring Boot application:

[[See Video to Reveal this Text or Code Snippet]]

The developer was following a guide on implementing i18n and found that, although the guide worked for others, it failed locally. Upon examining the code, the issue became evident. The localeResolver() method was defined incorrectly, leading to a StackOverflowError.

What’s Happening?

In the provided Java code snippet, the localeResolver method was incorrectly referencing itself:

[[See Video to Reveal this Text or Code Snippet]]

Each call to localeResolver() was inadvertently calling itself again, leading to an infinite loop that caused a StackOverflowError. This continual recursion is what triggered the BeanCreationException.

The Solution

The issue stems from the return statement inside the localeResolver() method. To fix this, the call to the method has to be changed so that it returns the created instance rather than calling the method again.

Correcting the Method

Here's how to correct the localeResolver() method:

Adjust the return statement to reference the local variable instead of invoking the method again.

Here’s the corrected code snippet:

[[See Video to Reveal this Text or Code Snippet]]

Additional Context

Bean Definitions: In Spring, beans are instantiated through methods annotated with -Bean. The framework expects these methods to return an object that will be managed as a Spring bean.

StackOverflowError: This particular error occurs when a method recurses excessively and exceeds the call stack. In this case, the misconfiguration led to endless calls to the localeResolver() method.

Conclusion

By removing the unintended recursive call and ensuring the method returns the created localeResolver instance, the BeanCreationException should be resolved.

If you're still having trouble after making these corrections, make sure to run your application with debug enabled to get detailed logs to help identify any other potential issues.

Now that you have this clear understanding, you can move forward with setting up internationalization in your Spring Boot application successfully!