68.1 Create your own FailureAnalyzer

[FailureAnalyzer is a great way to intercept an exception on startup and turn it into a human-readable message, wrapped into a [FailureAnalysis. Spring Boot provides such analyzer for application context related exceptions, JSR-303 validations and more. It is actually very easy to create your own.

AbstractFailureAnalyzer is a convenient extension of FailureAnalyzer that checks the presence of a specified exception type in the exception to handle. You can extend from that so that your implementation gets a chance to handle the exception only when it is actually present. If for whatever reason you can’t handle the exception, return null to let another implementation a chance to handle the exception.

FailureAnalyzer implementations are to be registered in a META-INF/spring.factories: the following registers ProjectConstraintViolationFailureAnalyzer:

org.springframework.boot.diagnostics.FailureAnalyzer=\
com.example.ProjectConstraintViolationFailureAnalyzer