In a Spring Boot application, how would I catch internally thrown exceptions that would otherwise escape to the client, but not Spring MVC exceptions?

Question

I have a class in my Spring Boot application that handles many specific exceptions automatically, using @ControllerAdvice:

@ControllerAdvice
@RequestMapping(produces = APPLICATION_JSON_UTF8_VALUE)
public class RestResponseEntityExceptionHandler {

For instance I catch this:

@ExceptionHandler(OptimisticLockingFailureException.class)
public ResponseEntity<ErrorDTO> optimisticLockingFailureException(final OptimisticLockingFailureException e) {
    LOGGER.info("Encountered OptimisticLockingFailureException", e);
    ErrorDTO errorDTO = new ErrorDTO("CONFLICT_ERROR", "Object was locked by ano user, please refresh and try again.");
    return new ResponseEntity<>(errorDTO, HttpStatus.CONFLICT);
}

And even low level database exceptions:

@ExceptionHandler(DataIntegrityViolationException.class)
public ResponseEntity<ErrorDTO> dataIntegrityViolationException(final DataIntegrityViolationException e) {

But sometimes still some exceptions escape to the client that I didn't handle specifically and didn't know about. I cannot predict the names of all exceptions in an increasingly complex application.

So I naively added this:

@ExceptionHandler(Exception.class)
protected ResponseEntity<ErrorDTO> exception(final Exception e) {
    ErrorDTO error = new ErrorDTO(
            "Test", "test");
    return new ResponseEntity<>(error, HttpStatus.BAD_REQUEST);
}

But this catches everything, even Spring MVC exceptions. So now if I do a request to some non-existing endpoint and normally Spring MVC handles this nicely, it now also is caught in my method and I don't want that.

How would I make it so all exceptions emitted after the entry point in my controllers are caught here so that the client never sees a stacktrace, but everything that Spring MVC handles before my code is even entered is handled normally?

Answer 1

You can try extending ResponseEntityExceptionHandler on your ControllerAdvice and overriding handleExceptionInternal if you need to have a common error message. I believe there are some things you would have to add to your application properties.