SpringBoot如何进行全局异常处理？

1.为什么需要全局异常处理？

在日常开发中，为了不抛出异常堆栈信息给前端页面，每次编写Controller层代码都要尽可能的catch住所有service层、dao层等异常，代码耦合性较高，且不美观，不利于后期维护。

应用场景是什么？

• 非常方便的去掉了try...catch这类冗杂难看的代码，有利于代码的整洁和优雅
• 自定义参数校验时候全局异常处理会捕获异常，将该异常统一返回给前端，省略很多if...else代码
• 当后端出现异常时，需要返回给前端一个友好的界面的时候就需要全局异常处理
• 因为异常时层层向上抛出的，为了避免控制台打印一长串异常信息

2.代码工程

实验目的

实现全局异常拦截

controller

package com.et.exception.controller;import com.et.exception.config.BizException;
import com.et.exception.model.User;
import org.springframework.web.bind.annotation.*;import java.util.HashMap;
import java.util.Map;@RestController
public class HelloWorldController {@RequestMapping("/hello")public Map<String, Object> showHelloWorld(){Map<String, Object> map = new HashMap<>();map.put("msg", "HelloWorld");return map;}@PostMapping("/user")public boolean insert(@RequestBody User user) {System.out.println("add...");if(user.getName()==null){throw  new BizException("-1","username is empty！");}return true;}@PutMapping("/user")public boolean update(@RequestBody User user) {System.out.println("update...");//mock NullExceptionString str=null;str.equals("111");return true;}@DeleteMapping("/user")public boolean delete(@RequestBody User user)  {System.out.println("delete...");//mock ExceptionInteger.parseInt("abc123");return true;}}

globe exception config

定义全局异常拦截类

package com.et.exception.config;import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.web.bind.annotation.ControllerAdvice;
import org.springframework.web.bind.annotation.ExceptionHandler;
import org.springframework.web.bind.annotation.ResponseBody;import javax.servlet.http.HttpServletRequest;@ControllerAdvice
public class GlobalExceptionHandler {private static final Logger logger = LoggerFactory.getLogger(GlobalExceptionHandler.class);/***process BizException* @param req* @param e* @return*/@ExceptionHandler(value = BizException.class)@ResponseBodypublic  ResultBody bizExceptionHandler(HttpServletRequest req, BizException e){logger.error("biz exception！the reason is：{}",e.getErrorMsg());return ResultBody.error(e.getErrorCode(),e.getErrorMsg());}/*** process NUllException* @param req* @param e* @return*/@ExceptionHandler(value =NullPointerException.class)@ResponseBodypublic ResultBody exceptionHandler(HttpServletRequest req, NullPointerException e){logger.error("null exception！the reason is：",e);return ResultBody.error(CommonEnum.BODY_NOT_MATCH);}/*** unkown Exception* @param req* @param e* @return*/@ExceptionHandler(value =Exception.class)@ResponseBodypublic ResultBody exceptionHandler(HttpServletRequest req, Exception e){logger.error("unkown Exception！the reason is:",e);return ResultBody.error(CommonEnum.INTERNAL_SERVER_ERROR);}
}

自定义业务异常

package com.et.exception.config;public class BizException extends RuntimeException {private static final long serialVersionUID = 1L;protected String errorCode;protected String errorMsg;public BizException() {super();}public BizException(BaseErrorInfoInterface errorInfoInterface) {super(errorInfoInterface.getResultCode());this.errorCode = errorInfoInterface.getResultCode();this.errorMsg = errorInfoInterface.getResultMsg();}public BizException(BaseErrorInfoInterface errorInfoInterface, Throwable cause) {super(errorInfoInterface.getResultCode(), cause);this.errorCode = errorInfoInterface.getResultCode();this.errorMsg = errorInfoInterface.getResultMsg();}public BizException(String errorMsg) {super(errorMsg);this.errorMsg = errorMsg;}public BizException(String errorCode, String errorMsg) {super(errorCode);this.errorCode = errorCode;this.errorMsg = errorMsg;}public BizException(String errorCode, String errorMsg, Throwable cause) {super(errorCode, cause);this.errorCode = errorCode;this.errorMsg = errorMsg;}public String getErrorCode() {return errorCode;}public void setErrorCode(String errorCode) {this.errorCode = errorCode;}public String getErrorMsg() {return errorMsg;}public void setErrorMsg(String errorMsg) {this.errorMsg = errorMsg;}public String getMessage() {return errorMsg;}@Overridepublic Throwable fillInStackTrace() {return this;}}

自定义返回结果

package com.et.exception.config;import com.alibaba.fastjson.JSONObject;public class ResultBody {private String code;private String message;private Object result;public ResultBody() {}public ResultBody(BaseErrorInfoInterface errorInfo) {this.code = errorInfo.getResultCode();this.message = errorInfo.getResultMsg();}public String getCode() {return code;}public void setCode(String code) {this.code = code;}public String getMessage() {return message;}public void setMessage(String message) {this.message = message;}public Object getResult() {return result;}public void setResult(Object result) {this.result = result;}public static ResultBody success() {return success(null);}public static ResultBody success(Object data) {ResultBody rb = new ResultBody();rb.setCode(CommonEnum.SUCCESS.getResultCode());rb.setMessage(CommonEnum.SUCCESS.getResultMsg());rb.setResult(data);return rb;}public static ResultBody error(BaseErrorInfoInterface errorInfo) {ResultBody rb = new ResultBody();rb.setCode(errorInfo.getResultCode());rb.setMessage(errorInfo.getResultMsg());rb.setResult(null);return rb;}public static ResultBody error(String code, String message) {ResultBody rb = new ResultBody();rb.setCode(code);rb.setMessage(message);rb.setResult(null);return rb;}public static ResultBody error( String message) {ResultBody rb = new ResultBody();rb.setCode("-1");rb.setMessage(message);rb.setResult(null);return rb;}@Overridepublic String toString() {return JSONObject.toJSONString(this);}}

实体类

package com.et.exception.model;import com.alibaba.fastjson.JSONObject;import java.io.Serializable;public class User implements Serializable {private static final long serialVersionUID = 1L;private int id;private String name;private int age;public User(){}public int getId() {return id;}public void setId(int id) {this.id = id;}public String getName() {return name;}public void setName(String name) {this.name = name;}public int getAge() {return age;}public void setAge(int age) {this.age = age;}public String toString() {return JSONObject.toJSONString(this);}
}

以上只是一些关键代码，所有代码请参见下面代码仓库

代码仓库

• GitHub - Harries/springboot-demo: a simple springboot demo with some components for example: redis,solr,rockmq and so on.(exception)

3.测试

启动Spring Boot项目

模拟业务异常

模拟null异常

​编辑0%模拟其他异常

4.引用

• SpringBoot如何进行全局异常处理？ | Harries Blog™