如何使用@ExceptionHandler 捕获 HTTP 405“不允许的方法”异常？

Question

我创建了一个 REST 应用程序并添加了一个类来处理异常：

@RestControllerAdvice(basePackages = "com.foxminded.university.api.controller")
public class ApiGlobalExceptionHandler extends ResponseEntityExceptionHandler {
    private static final String API_UNHANDLED_EXCEPTION = "REST API reached unhandled exception: %s";
    private static final HttpStatus internalServerError = HttpStatus.INTERNAL_SERVER_ERROR;

    @ExceptionHandler(Exception.class)
    public ResponseEntity<Object> handle(Exception e) {
        ExceptionDetail exceptionDetail = new ExceptionDetail(
            String.format(API_UNHANDLED_EXCEPTION, e.getMessage()),
            internalServerError,
            ZonedDateTime.now(ZoneId.systemDefault()));
        return new ResponseEntity<Object>(exceptionDetail, internalServerError);
    }

    @Override
    public ResponseEntity<Object> handleTypeMismatch(
        TypeMismatchException ex, HttpHeaders headers, HttpStatus status, WebRequest request) {
        ExceptionDetail exceptionDetail = new ExceptionDetail(
            String.format(API_UNHANDLED_EXCEPTION, ex.getMessage()),
            internalServerError,
            ZonedDateTime.now(ZoneId.systemDefault()));
        return new ResponseEntity<Object>(exceptionDetail, internalServerError);
    }

    @Override
    public ResponseEntity<Object> handleMethodArgumentNotValid(MethodArgumentNotValidException e, HttpHeaders headers,
        HttpStatus status, WebRequest request) {
        ExceptionDetail exceptionDetail = new ExceptionDetail(
            String.format(API_UNHANDLED_EXCEPTION, e.getMessage()),
            internalServerError,
            ZonedDateTime.now(ZoneId.systemDefault()),
            e.getBindingResult().getFieldErrors());
        return new ResponseEntity<Object>(exceptionDetail, internalServerError);
    }
}

当我通过邮递员 http://localhost:8080/api/groups/jkjk 而不是 http://localhost:8080/api/groups 发送错误的发布请求时

它抛出了一个我在调试时无法捕获初始化的异常，无论是在 ApiGlobalExceptionHandler 类中还是在 ResponseEntityExceptionHandler 类中：

{
    "timestamp": 1604171144423,
    "status": 405,
    "error": "Method Not Allowed",
    "message": "",
    "path": "/api/groups/jkjk"
}

我可以捕获的所有其他异常。如何捕获此异常以添加自定义处理？

Answer 1

您只需在其签名中添加一个带有MethodNotAllowedException 的新方法。

@ExceptionHandler(value = MethodNotAllowedException.class)
public ResponseEntity<Object> handleMethodNotAllowedExceptionException(MethodNotAllowedException ex) {
    return buildResponseEntity(HttpStatus.METHOD_NOT_ALLOWED, null, null, ex.getMessage(), null);
}

private ResponseEntity<Object> buildResponseEntity(HttpStatus status, HttpHeaders headers, Integer internalCode, String message, List<Object> errors) {
    ResponseBase response = new ResponseBase() //A generic ResponseBase class
            .success(false)
            .message(message)
            .resultCode(internalCode != null ? internalCode : status.value())
            .errors(errors != null
                    ? errors.stream().filter(Objects::nonNull).map(Objects::toString).collect(Collectors.toList())
                    : null);
    
    return new ResponseEntity<>((Object) response, headers, status);
}

您可以随意自定义buildResponseEntity。

更新

我重新审视了我的答案，因为它不符合您的要求。所以，它是这样的：

我发送一个接受GET 的方法的post 请求。这将触发 Request method 'POST' not supported，如下所示。

org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerMapping.查找路径 /v1/user/profile/1 的处理程序方法 org.springframework.web.servlet.mvc.method.annotation.ExceptionHandlerExceptionResolver.Resolving 来自处理程序 [null] 的异常：org.springframework.web.HttpRequestMethodNotSupportedException：不支持请求方法“POST” org.springframework.beans.factory.support.DefaultListableBeanFactory.Returning 单例 bean 'ethGlobalExceptionHandler' 的缓存实例

在这种情况下，无需添加 @ExceptionHandler(value = HttpRequestMethodNotSupportedException.class).

其实如果这样做的话，会抛出下面的错误（因为已经处理过了），

java.lang.IllegalStateException: Ambiguous @ExceptionHandler method mapped for [class org.springframework.web.HttpRequestMethodNotSupportedException]:....

所以，解决办法是：

@Override
protected ResponseEntity<Object> handleHttpRequestMethodNotSupported(HttpRequestMethodNotSupportedException ex,
        HttpHeaders headers, HttpStatus status, WebRequest request) {
    return buildResponseEntity(HttpStatus.METHOD_NOT_ALLOWED, headers, null, ex.getMessage(), Arrays.asList(""));
}

Answer 2

我在这里找到了解释Custom handling for 405 error with Spring Web MVC

上面写着The reason your @ExceptionHandler annotated method never catches your exception is because these ExceptionHandler annotated methods are invoked after a successful Spring controller handler mapping is found. However, your exception is raised before that.

并且解决方案不是从 ResponseEntityExceptionHandler 类扩展，而是从 DefaultHandlerExceptionResolver 扩展并覆盖它的 handleHttpRequestMethodNotSupported 方法。