JAVA 使用 Spring MVC 无侵入式的统一接口格式返回

冷不防 2022-12-07 12:50 150阅读 0赞

1，创建 Result 类

@Getter
    @ToString
    public class Result<T> { 
    
        /** * 业务错误吗 */
        private Integer code;
    
        private String message;
    
        private T data;
    
        private Result(ResultStatus resultStatus, T data) { 
            this.code = resultStatus.getCode();
            this.message = resultStatus.getMessage();
            this.data = data;
        }
        /** 业务成功返回业务代码和描述信息 */
        private static  Result<Void> success(){ 
            return  new Result<Void>(ResultStatus.SUCCESS,null);
        }
        /** 业务成功返回业务代码,描述和返回的参数 */
        public static <T> Result<T> success(T data) { 
            return new Result<T>(ResultStatus.SUCCESS, data);
        }
    
        /** 业务成功返回业务代码,描述和返回的参数 */
        public static <T> Result<T> success(ResultStatus resultStatus, T data) { 
            if (resultStatus == null) { 
                return success(data);
            }
            return new Result<T>(resultStatus, data);
        }
    
        /** 业务异常返回业务代码和描述信息 */
        public static <T> Result<T> failure() { 
            return new Result<T>(ResultStatus.INTERNAL_SERVER_ERROR, null);
        }
        /** 业务异常返回业务代码,描述和返回的参数 */
        public static <T> Result<T> failure(ResultStatus resultStatus) { 
            return failure(resultStatus, null);
        }
    
        /** 业务异常返回业务代码,描述和返回的参数 */
        public static <T> Result<T> failure(ResultStatus resultStatus, T data) { 
            if (resultStatus == null) { 
                return new Result<T>(ResultStatus.INTERNAL_SERVER_ERROR, null);
            }
            return new Result<T>(resultStatus, data);
        }

2，创建 定义状态码 Result Status 枚举类

@ToString
    @Getter
    public enum ResultStatus { 
        /** * 成功 */
        SUCCESS(HttpStatus.OK,200,"OK"),
        /** * 错误的请求 */
        BAD_REQUEST(HttpStatus.BAD_REQUEST,400,"Bad Request"),
        /** * 内部服务器错误 */
        INTERNAL_SERVER_ERROR(HttpStatus.INTERNAL_SERVER_ERROR, 500, "Internal Server Error");
    
    
        /** * 返回的HTTP 状态码，符合http 请求 */
    
        private HttpStatus httpStatus;
        /** * 业务异常码 */
        private Integer code;
        /** * 业务异常信息描述 */
        private String message;
    
        ResultStatus(HttpStatus httpStatus,Integer code,String message){ 
            this.httpStatus=httpStatus;
            this.code=code;
            this.message=message;
        }
    }

3，创建一个 标记 在类和方法上可以 自动化生成 result 返回格式 注解

@Retention(RetentionPolicy.RUNTIME)
    @Target({ ElementType.TYPE, ElementType.METHOD})
    @Documented
    @ResponseBody
    public @interface ResponseResultBody { 
    
    }

4，创建 Result Excrption 返回 异常

@Getter
    public class ResultException  extends Exception { 
        ResultStatus resultStatus;
    
        public ResultException() { 
            this(ResultStatus.INTERNAL_SERVER_ERROR);
        }
    
        public ResultException(ResultStatus resultStatus) { 
            super(resultStatus.getMessage());
            this.resultStatus = resultStatus;
        }
    
    }

5，创建一个 Advice 通知类 统一处理

/** * 统一异常处理 * @ProjectName: quartz * @Package: com.weng.quartz.advice * @ClassName: ResponseResultBodyAdvice * @Author: wym * @Date: 2020/9/9 10:46 * @Version: 1.0 */
    @RestControllerAdvice
    public class ResponseResultBodyAdvice implements ResponseBodyAdvice<Object> { 
        private static final Class<? extends Annotation> ANNOTATION_TYPE = ResponseResultBody.class;
    
        /** * 判断类或者方法是否使用了 @ResponseResultBody */
        @Override
        public boolean supports(MethodParameter returnType, Class<? extends HttpMessageConverter<?>> converterType) { 
            return AnnotatedElementUtils.hasAnnotation(returnType.getContainingClass(), ANNOTATION_TYPE) || returnType.hasMethodAnnotation(ANNOTATION_TYPE);
        }
    
        /** * 当类或者方法使用了 @ResponseResultBody 就会调用这个方法 */
        @Override
        public Object beforeBodyWrite(Object body, MethodParameter returnType, MediaType selectedContentType, Class<? extends HttpMessageConverter<?>> selectedConverterType, ServerHttpRequest request, ServerHttpResponse response) { 
            // 防止重复包裹的问题出现
            if (body instanceof Result) { 
                return body;
            }
            //默认返回 SUCCESS
            return Result.success(body);
        }
        /** * 提供对标准Spring MVC异常的处理 * * @param ex the target exception * @param request the current request */
        @ExceptionHandler(Exception.class)
        public final ResponseEntity<Result<?>> exceptionHandler(Exception ex, WebRequest request) { 
            HttpHeaders headers = new HttpHeaders();
            if (ex instanceof ResultException) { 
                return this.handleResultException((ResultException) ex, headers, request);
            }
            // TODO: 2019/10/05 galaxy 这里可以自定义其他的异常拦截
            return this.handleException(ex, headers, request);
        }
    
    
        /** 对ResultException类返回返回结果的处理 */
        protected ResponseEntity<Result<?>> handleResultException(ResultException ex, HttpHeaders headers, WebRequest request) { 
            Result<?> body = Result.failure(ex.getResultStatus());
            HttpStatus status = ex.getResultStatus().getHttpStatus();
            return this.handleExceptionInternal(ex, body, headers, status, request);
        }
    
        /** 异常类的统一处理 */
        protected ResponseEntity<Result<?>> handleException(Exception ex, HttpHeaders headers, WebRequest request) { 
            Result<?> body = Result.failure();
            HttpStatus status = HttpStatus.INTERNAL_SERVER_ERROR;
            return this.handleExceptionInternal(ex, body, headers, status, request);
        }
    
        /** * org.springframework.web.servlet.mvc.method.annotation.ResponseEntityExceptionHandler#handleExceptionInternal(java.lang.Exception, java.lang.Object, org.springframework.http.HttpHeaders, org.springframework.http.HttpStatus, org.springframework.web.context.request.WebRequest) * <p> * A single place to customize the response body of all exception types. * <p>The default implementation sets the {@link WebUtils#ERROR_EXCEPTION_ATTRIBUTE} * request attribute and creates a {@link ResponseEntity} from the given * body, headers, and status. */
        protected ResponseEntity<Result<?>> handleExceptionInternal(
                Exception ex, Result<?> body, HttpHeaders headers, HttpStatus status, WebRequest request) { 
    
            if (HttpStatus.INTERNAL_SERVER_ERROR.equals(status)) { 
                request.setAttribute(WebUtils.ERROR_EXCEPTION_ATTRIBUTE, ex, WebRequest.SCOPE_REQUEST);
            }
            return new ResponseEntity<>(body, headers, status);
        }
    
    
    }

测试方法：

@RestController
    @RequestMapping("/helloResult")
    @ResponseResultBody
    public class HelloResultController { 
        private static final HashMap<String, Object> INFO;
    
        static { 
            INFO = new HashMap<String, Object>();
            INFO.put("name", "galaxy");
            INFO.put("age", "70");
        }
    
        @GetMapping("hello")
        public HashMap<String, Object> hello() { 
            return INFO;
        }
    
        /** 测试重复包裹 */
        @GetMapping("result")
        public Result<Map<String, Object>> helloResult() { 
            return Result.success(INFO);
        }
    
        @GetMapping("helloError")
        public HashMap<String, Object> helloError() throws Exception { 
            throw new Exception("helloError");
        }
    
        @GetMapping("helloMyError")
        public HashMap<String, Object> helloMyError() throws Exception { 
            throw new ResultException();
        }
    }

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlbmc3NA_size_16_color_FFFFFF_t_70_pic_center]

自动将其包含 在date 中

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