Spring: Different exception handler for RestController and Controller

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In Spring you can set up “global” exception handler via @ControllerAdvice and @ExceptionHandler annotation. I’m trying to utilize this mechanism to have two global exception handlers:

  • RestControllerExceptionHandler – which should return error responses as json for any controller annotated with @RestController
  • ControllerExceptionHandler – which should print error message to the screen for any other controller (annottated with @Controller)

The problem is that when I declare these two exception handlers spring always uses the ControllerExceptionHandler and never RestControllerExceptionHandler to handle the exception.

How to make this work ?
BTW: I tried to use @Order annotation but this does not seem to work.

Here are my exception handlers:

// should handle all exception for classes annotated with         
@ControllerAdvice(annotations = RestController.class)
public class RestControllerExceptionHandler {


  @ExceptionHandler(Exception.class)
  public ResponseEntity<ErrorResponse> handleUnexpectedException(Exception e) {

    // below object should be serialized to json
    ErrorResponse errorResponse = new ErrorResponse("asdasd"); 

    return new ResponseEntity<ErrorResponse>(errorResponse, HttpStatus.INTERNAL_SERVER_ERROR);
  }

// should handle exceptions for all the other controllers
@ControllerAdvice(annotations = Controller.class)
public class ControllerExceptionHandler {


  @ExceptionHandler(Exception.class)
  public ResponseEntity<String> handleUnexpectedException(Exception e) {
    return new ResponseEntity<String>("Unexpected exception, HttpStatus.INTERNAL_SERVER_ERROR);
  }


}
}

When I remove ControllerExceptionHandler than RestControllerExceptionHandler is correctly called by spring (only for classes annotated with @RestController)…. but when I add ControllerExceptionHandler than all goes via ControllerExceptionHandler. Why?

Answer

After some deeper investigation it seems that the alphabetical order matters :/.

When I renamed my RestControllerExceptionHandler to ARestControllerExceptionHandler (which alphabetically precedes ControllerExceptionHandler) all works as expected! ARestControllerExceptionHandler correctly handles exceptions from RestControllers and ControllerExceptionHandler handles exception from other controllers.

I created a bug in spring for this: https://jira.spring.io/browse/SPR-15432

— EDIT:

I received the answer for SPR-15432 where it is suggested that this case can be solved with @Order (org.springframework.core.annotation.Order) annotation or by implementing Ordered interface.

This did not work for me before, but it seems that I have imported wrong @Order annotation. (from log4j2 instead of spring). After fixing this it works. Fixed version is following:

// should handle all exception for classes annotated with         
@ControllerAdvice(annotations = RestController.class)
@Order(1) // NOTE: order 1 here
public class RestControllerExceptionHandler {


  @ExceptionHandler(Exception.class)
  public ResponseEntity<ErrorResponse> handleUnexpectedException(Exception e) {

    // below object should be serialized to json
    ErrorResponse errorResponse = new ErrorResponse("asdasd"); 

    return new ResponseEntity<ErrorResponse>(errorResponse, HttpStatus.INTERNAL_SERVER_ERROR);
  }
}
// should handle exceptions for all the other controllers
@ControllerAdvice(annotations = Controller.class)
@Order(2)  // NOTE: order 2 here
public class ControllerExceptionHandler {


  @ExceptionHandler(Exception.class)
  public ResponseEntity<String> handleUnexpectedException(Exception e) {
    return new ResponseEntity<String>("Unexpected exception, HttpStatus.INTERNAL_SERVER_ERROR);
  }
}

Attribution
Source : Link , Question Author : walkeros , Answer Author : walkeros

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