springboot 异常处理的helloworld的Demo

秒速五厘米 2022-02-14 03:28 178阅读 0赞

# 第一步:maven构建 #

springboot 引入web

# 第二步:准备实体类javabean #

public class ErrorResponseEntity {
        private int code;
        private String message;
    
    //get set conduct
    }

# 第三步:准备一个自定义异常 #

public class CustomException extends RuntimeException {
        private static final long serialVersionUID = 4564124491192825748L;
    
        private int code;
    
        public CustomException() {
            super();
        }
    
        public int getCode() {
            return code;
        }
    
        public void setCode(int code) {
            this.code = code;
        }
    
        public CustomException(String message, int code) {
            super(message);
            this.setCode(code);
        }
    }

# 第四步:配置文件-全局异常处理 #

@RestControllerAdvice
    public class GlobalExceptionHandler extends ResponseEntityExceptionHandler {
    
        @ExceptionHandler(CustomException.class)
        public ErrorResponseEntity customExceptionHandler(HttpServletRequest request, final Exception e, HttpServletResponse response) {
            response.setStatus(HttpStatus.BAD_REQUEST.value());
            CustomException exception = (CustomException) e;
            return new ErrorResponseEntity(exception.getCode(), exception.getMessage());
        }
    
        @ExceptionHandler(RuntimeException.class)
        public ErrorResponseEntity runtimeExceptionHandler(HttpServletRequest request, final Exception e, HttpServletResponse response) {
            response.setStatus(HttpStatus.BAD_REQUEST.value());
            CustomException exception = (CustomException) e;
            return new ErrorResponseEntity(400, exception.getMessage());
        }
    
        /**
         * 通用的接口映射异常处理方
         */
        @Override
        protected ResponseEntity<Object> handleExceptionInternal(Exception ex, Object body, HttpHeaders headers, HttpStatus status, WebRequest request) {
            if (ex instanceof MethodArgumentNotValidException) {
                MethodArgumentNotValidException exception = (MethodArgumentNotValidException) ex;
                return new ResponseEntity<>(new ErrorResponseEntity(status.value(), exception.getBindingResult().getAllErrors().get(0).getDefaultMessage()), status);
            }
            if (ex instanceof MethodArgumentTypeMismatchException) {
                MethodArgumentTypeMismatchException exception = (MethodArgumentTypeMismatchException) ex;
                logger.error("参数转换失败，方法：" + exception.getParameter().getMethod().getName() + "，参数：" + exception.getName()
                        + ",信息：" + exception.getLocalizedMessage());
                return new ResponseEntity<>(new ErrorResponseEntity(status.value(), "参数转换失败"), status);
            }
            return new ResponseEntity<>(new ErrorResponseEntity(status.value(), "参数转换失败"), status);
        }
    }

# 第五步:写几个controller来试试看 #

@Controller  
public class TestController \{  
@GetMapping("/test1")  
public String test1() \{  
int i = 10 / 0;  
return “test1”;  
\}

@GetMapping("/test2")
    @ResponseBody
    public Map<String, String> test2() {
        Map<String, String> result = new HashMap<>(16);
        // TODO 直接捕获所有代码块，然后在 cache
        try {
            int i = 10 / 0;
            result.put("code", "200");
            result.put("data", "具体返回的结果集");
        } catch (Exception e) {
            result.put("code", "500");
            result.put("message", "请求错误");
        }
        return result;
    }
    
    @GetMapping("/test3")
    @ResponseBody
    public String test3(Integer num) {
        if (num == null) {
            throw new CustomException("num不能为空", 400);
        }
        if (num == 0) {
            throw new CustomException("被除数不能为零", 888);
        }
        int i = 10 / num;
        return "result:" + i;
    }

# 结果展示 #

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzM0NDUzMzAw_size_16_color_FFFFFF_t_70]  
![在这里插入图片描述][20190425171811464.png]  
![在这里插入图片描述][20190425171833363.png]

![在这里插入图片描述][2019042517190228.png]  
![在这里插入图片描述][20190425171922460.png]  
![在这里插入图片描述][20190425171937996.png]

[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzM0NDUzMzAw_size_16_color_FFFFFF_t_70]: /images/20220214/d0bb459bc0b340728c253bf12ad653bc.png
[20190425171811464.png]: /images/20220214/a1ca6f150f53479c96e917bcc70f1282.png
[20190425171833363.png]: /images/20220214/313252b396bd4520b5be0d69b40b3624.png
[2019042517190228.png]: /images/20220214/f156f592e3564fc785281b019ae1ac04.png
[20190425171922460.png]: /images/20220214/4a2bbcc43d39444a96b492676809f421.png
[20190425171937996.png]: /images/20220214/7192ff02499942c490f6fb2548785b3d.png