SpringBoot RESTful 应用中的异常处理小结 [转]

Posted 2020-11-24 tangdatou

转自 https://segmentfault.com/a/1190000006749441

 

在J2EE项目的开发中，不管是对底层的数据库操作过程，还是业务层的处理过程，还是控制层的处理过程，都不可避免会遇到各种可预知的、不可预知的异常需要处理。每个过程都单独处理异常，系统的代码耦合度高，工作量大且不好统一，维护的工作量也很大。

这里使用

@ControllerAdvice ,@ExceptionHandler(value = BaseException.class)

 

 

需要注意的是, ExceptionHandler 的优先级比 ControllerAdvice 高, 即 Controller 抛出的异常如果既可以让 ExceptionHandler 标注的方法处理, 又可以让 ControllerAdvice 标注的类中的方法处理, 则优先让 ExceptionHandler 标注的方法处理.

@RestController
@ControllerAdvice
public class GlobalExceptionHandler {
    private Logger logger = LoggerFactory.getLogger("GlobalExceptionHandler");

    @ExceptionHandler(value = BaseException.class)
    @ResponseBody
    public Object baseErrorHandler(HttpServletRequest req, Exception e) throws Exception {
        logger.error("---BaseException Handler---Host {} invokes url {} ERROR: {}", req.getRemoteHost(), req.getRequestURL(), e.getMessage());
        return "---BaseException Handler---:" + e.getMessage();
    }

    @ExceptionHandler(value = Exception.class)
    @ResponseBody
    public Object defaultErrorHandler(HttpServletRequest req, Exception ex) throws Exception {
        logger.error("---DefaultException Handler---Host {} invokes url {} ERROR: {}", req.getRemoteHost(), req.getRequestURL(), ex.getMessage());
        JSONObject json = new JSONObject();
        json.put("errorMsg", ex.getMessage());
        json.put("errorCode", HttpStatus.BAD_REQUEST);
        return ResponseEntity.badRequest().body(json);
    }
}

　　

@RestController
public class DemoController {
    private Logger logger = LoggerFactory.getLogger("GlobalExceptionHandler");

    @RequestMapping("/ex1")
    public Object throwBaseException() throws Exception {
        throw new BaseException("This is BaseException.");
    }

    @RequestMapping("/ex2")
    public Object throwMyException1() throws Exception {
        throw new MyException1("This is MyException1.");
    }

    @RequestMapping("/ex3")
    public Object throwMyException2() throws Exception {
        throw new MyException2("This is MyException1.");
    }

    @RequestMapping("/ex4")
    public Object throwIOException() throws Exception {
        throw new IOException("This is IOException.");
    }

    @RequestMapping("/ex5")
    public Object throwNullPointerException() throws Exception {
        throw new NullPointerException("This is NullPointerException.");
    }
}