从WebSocket消息处理MethodArgumentNotValidException

Question

@Controller
public class MessageThreadController {
    /* A plain XHR post request with a JSON body to match MessageThread. */
    @RequestMapping(
        headers={"Accept=application/hal+json", "Content-Type=application/json", "X-Requested-With=XMLHttpRequest"},
        method={RequestMethod.POST},
        produces="application/hal+json",
        value="/api/unsecure/thread/create")
    public HttpEntity createPost(@Valid @RequestBody MessageThread messageThread) throws Exception {
        return ResponseEntity.ok("valid");
    }

    /* The same request above but for WebSocket.*/
    @MessageMapping("/api/secure/thread/create")
    @SendToUser("/api/secure/broadcast")
    public HttpEntity createMessage(@Valid @RequestBody MessageThread messageThread) throws Exception {
        return ResponseEntity.ok("valid");
    }
}

我有一个@ControllerAdvise来捕获可能发生的异常:

@ControllerAdvice
public class MessageThreadControllerAdvice {
    private static final Logger log = LoggerFactory.getLogger(MessageThreadControllerAdvice.class);

    /* MessageThreadController.createPost() validation exception are handled here. */
    @ExceptionHandler(org.springframework.web.bind.MethodArgumentNotValidException.class)
    public void methodArgumentNotValidExceptionHandler(
        org.springframework.web.bind.MethodArgumentNotValidException e) {
        log.trace("methodArgumentNotValidExceptionHandler");
    }

    /* MessageThreadController.createMessage() validation exception are handled here. */
    @ExceptionHandler(org.springframework.messaging.handler.annotation.support.MethodArgumentNotValidException.class)
    @SendToUser("/api/secure/broadcast")
    public void methodArgumentNotValidWebSocketExceptionHandler(
        org.springframework.messaging.handler.annotation.support.MethodArgumentNotValidException e) {
        log.trace("methodArgumentNotValidWebSocketExceptionHandler");
    }

    /* All exceptions are handled here. */
    @ExceptionHandler
    @SendToUser("/api/secure/broadcast")
    public void exceptionHandler(Exception e) {
        log.trace("exceptionHandler");
    }
}

这里是有问题的对象：

@Getter @Setter
public class MessageThread {
    @Size(min=1, message="{validation.userIds.empty}")
    @NotNull(message="{validation.userIds.null}")
    private Set<BigInteger> userIds;
}

如果在MessageThreadController.createPost()和MessageThreadController.createMessage()中发送以下JSON正文：

{"userIds":[]}

如何处理在websocket消息上引发的MethodArgumentNotValidException？

Answer 1

您可以使用@MessageExceptionHandler注释来注释@ControllerAdvise方法。

@ControllerAdvice
public class MessageThreadControllerAdvice {
    private static final Logger log = LoggerFactory.getLogger(MessageThreadControllerAdvice.class);

    /* MessageThreadController.createPost() validation exception are handled here. */
    @ExceptionHandler(org.springframework.web.bind.MethodArgumentNotValidException.class)
    public void methodArgumentNotValidExceptionHandler(
        org.springframework.web.bind.MethodArgumentNotValidException e) {
        log.trace("methodArgumentNotValidExceptionHandler");
    }

    /* MessageThreadController.createMessage() validation exception are handled here. */
    @MessageExceptionHandler(org.springframework.messaging.handler.annotation.support.MethodArgumentNotValidException.class)
    @SendToUser("/api/secure/broadcast")
    public void methodArgumentNotValidWebSocketExceptionHandler(
        org.springframework.messaging.handler.annotation.support.MethodArgumentNotValidException e) {
        log.trace("methodArgumentNotValidWebSocketExceptionHandler");
    }

    /* All exceptions are handled here. */
    @ExceptionHandler
    @SendToUser("/api/secure/broadcast")
    public void exceptionHandler(Exception e) {
        log.trace("exceptionHandler");
    }
}

这个注释也可以应用在@controller级别。

请注意，自Spring4.2以来，@ControllerAdvise级别支持此注释。