Spring Boot Exception Handling @ExceptionHandler and @ControllerAdvice

Spring 3.2 brings support for a global @ExceptionHandler with the @ControllerAdvice annotation.

This enables a mechanism that breaks away from the older MVC model and makes use of ResponseEntity along with the type safety and flexibility of @ExceptionHandler:

public class RestResponseEntityExceptionHandler 
  extends ResponseEntityExceptionHandler {

      = { IllegalArgumentException.class, IllegalStateException.class })
    protected ResponseEntity<Object> handleConflict(
      RuntimeException ex, WebRequest request) {
        String bodyOfResponse = "This should be application specific";
        return handleExceptionInternal(ex, bodyOfResponse, 
          new HttpHeaders(), HttpStatus.CONFLICT, request);

The@ControllerAdvice annotation allows us to consolidate our multiple, scattered @ExceptionHandlers from before into a single, global error handling component.

The actual mechanism is extremely simple but also very flexible:

  • It gives us full control over the body of the response as well as the status code.
  • It provides mapping of several exceptions to the same method, to be handled together.
  • It makes good use of the newer RESTful ResposeEntity response.

One thing to keep in mind here is to match the exceptions declared with @ExceptionHandler to the exception used as the argument of the method.

If these don’t match, the compiler will not complain — no reason it should — and Spring will not complain either.

However, when the exception is actually thrown at runtime, the exception resolving mechanism will fail with:

java.lang.IllegalStateException: No suitable resolver for argument [0] [type=...]
HandlerMethod details: ...

Reference :

Leave a Comment