Solving HV000028: Unexpected Exception During isValid Call in Hibernate/Spring Custom Validators

Описание: Encountering `HV000028` errors while using custom validators in Spring Boot? Discover how to resolve autowiring issues with Hibernate's Validator!
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Solving HV000028: Unexpected Exception During isValid Call in Hibernate/Spring Custom Validators

When developing applications using Spring Boot and Hibernate, you might encounter the error message HV000028: Unexpected exception during isValid call. This issue often occurs while implementing custom constraint validators, particularly when using autowired repositories within those validators. If you find that your custom validator's logic throws this error even though everything else works as intended, you are not alone. Let's break down the problem and see how we can resolve it effectively.

Understanding the Problem

In custom validators, the isValid method is crucial for validating the objects being processed. However, if you attempt to use autowired repositories in this method without proper configuration, the autowiring may fail, leading to unexpected exceptions. In this specific scenario, the code snippet shows that despite the repository method findById returning valid data, an error occurs when trying to access the repository within the isValid function of the custom validator.

The Code Snippet

Here’s a brief look at the relevant code causing the issue:

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

Why This Happens

The root cause of the problem is that the autowiring process does not function correctly within the ConstraintValidator. Validator instances are instantiated by Hibernate, which may not honor Spring's dependency injection mechanisms. As a result, when the findById method tries to be called, it fails because the propertyrepository is not properly autowired.

Solution: Proper Configuration for Autowiring

To resolve the autowiring issue and ensure that your custom validator can use the Spring-managed beans correctly, you need to follow a specific configuration process. Here’s how to do it:

Step 1: Create a Hibernate Validator Customizer

You will need to implement a custom configuration class that integrates Spring’s Validator with Hibernate's Validator. Here’s a sample code for this configuration:

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

Step 2: Enable Component Scanning

Ensure that your Spring Boot application scans for components properly. This is usually handled automatically, but double-check your main application class to include the necessary annotations like @ SpringBootApplication.

Step 3: Re-Test Your Application

After adding the customizer, re-test your application by triggering the isValid method from your custom validator. It should now work without throwing the unexpected exception, and you can access your repository without issues.

Conclusion

By following the above steps and implementing a Hibernate Validator Customizer, you can resolve the HV000028: Unexpected exception during isValid call error effectively. This not only enhances your custom validation logic but ensures your application runs smoothly. Keep in mind the importance of correct configuration and the role of Spring’s dependency injection in making your components work together seamlessly.

With this solution, you can focus on developing your features without being hampered by unexpected errors in your code. Happy coding!