How to handle validation errors and exceptions in a RESTful Spring MVC controller?

Question

For example, how to handle validation errors and possible exceptions in this controller action method:

@RequestMapping(method = POST)
@ResponseBody
public FooDto create(@Valid FooDTO fooDto, BindingResult bindingResult) {
    if (bindingResult.hasErrors()) {
        return null; // what to do here?
                     // how to let the client know something has gone wrong?
    } else {
        fooDao.insertFoo(fooDto); // What to do if an exception gets thrown here?
                                  // What to send back to the client?
        return fooDto;
    }
}

Send back an appropriate error response and/or code. I don't understand the question, I guess. — Dave Newton, Feb 12 '12 at 03:16
The action returns a `FooDTO`, how to send back an appropriate response with some validation error messages? — K Everest, Feb 12 '12 at 06:12

score 16 · Accepted Answer · answered Feb 12 '12 at 10:19

16

Throw an exception if you have an error, and then use @ExceptionHandler to annotate another method which will then handle the exception and render the appropriate response.

answered Feb 12 '12 at 10:19

skaffman

398,947
96
818
769

4

He could even use `throw new BindException(bindingResult)` and then have handler for BindException. – Adam Gent Aug 21 '12 at 13:41
5

He shouldn't even have to explicitly throw a `BindException`. Just remove the `BindingResult` argument from the method and spring will throw a `BindException` if there are any validation errors. And the exception handler method can access all the error details because `BindException` implements `BindingResult` and `Errors`. – JCoster22 May 15 '16 at 05:48

score 5 · Answer 2 · edited May 18 '15 at 05:22

5

@RequestMapping(method = POST)
@ResponseBody
public FooDto create(@Valid FooDTO fooDto) {
//Do my business logic here
    return fooDto;

}

Create a n exception handler:

@ExceptionHandler( MethodArgumentNotValidException.class)
@ResponseBody
@ResponseStatus(value = org.springframework.http.HttpStatus.BAD_REQUEST)
protected CustomExceptionResponse handleDMSRESTException(MethodArgumentNotValidException objException)
{

    return formatException(objException);
}

I don't know if this is the correct approach i am following. I would appreciate if you could tell me what you have done for this issue.

edited May 18 '15 at 05:22

valar morghulis

2,007
27
34

answered May 18 '15 at 04:38

Albert Pinto

392
2
6
17

1

This will not work since there is already handler method for MethodArgumentNotValidException defined in ResponseEntityExceptionHandler, check this asnwer for further details, https://stackoverflow.com/a/38282563/4184240 – ahmedjaad Jul 13 '18 at 15:07

How to handle validation errors and exceptions in a RESTful Spring MVC controller?

2 Answers2

Linked