Spring Boot中的全局异常处理：@RestControllerAdvice的应用

在现代Web开发中，异常处理是一个不可或缺的部分。良好的异常处理不仅能提高系统的健壮性，还能提升用户体验。在Spring Boot中，全局异常处理的实现可以通过使用@RestControllerAdvice注解来完成。本文将详细介绍如何使用@RestControllerAdvice和@ExceptionHandler来统一处理异常，并给出具体的实现示例。

1. @RestControllerAdvice概述

@RestControllerAdvice是Spring MVC提供的一个功能强大的注解，用于全局处理控制器中的异常。它相当于@ControllerAdvice和@ResponseBody的组合，可以用于定义以下三种功能：

1. @ExceptionHandler：处理特定的异常，并将响应返回给前端。
2. @InitBinder：预处理Web请求数据的绑定。
3. @ModelAttribute：将数据绑定到模型中，以便在控制器的@RequestMapping方法中使用。

@RestControllerAdvice自动被Spring的组件扫描机制检测到，若应用通过MVC命令空间或MVC Java编程方式配置，该功能默认自动开启。

2. 实现全局异常处理

在实现全局异常处理时，我们通常会定义一个异常处理类，这个类中包含多个异常处理方法，每个方法对应一种或多种异常类型。下面是一个典型的实现示例。

2.1 全局异常处理器

import com.sugon.cloud.lowcode.result.ReturnResult;
import lombok.extern.slf4j.Slf4j;
import org.mybatis.spring.MyBatisSystemException;
import org.springframework.web.HttpRequestMethodNotSupportedException;
import org.springframework.web.bind.annotation.ExceptionHandler;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.bind.annotation.RestControllerAdvice;import javax.naming.AuthenticationException;
import javax.servlet.http.HttpServletRequest;import static com.sugon.cloud.lowcode.constants.SplitCharacter.LEFT_PARENTHESES;
import static com.sugon.cloud.lowcode.constants.SplitCharacter.RIGHT_PARENTHESES;
import static com.sugon.cloud.lowcode.result.CodeMessageEnum.*;@RestControllerAdvice
@Slf4j
public class GlobalExceptionHandler {@ExceptionHandler(value = BizException.class)@ResponseBodypublic ReturnResult bizExceptionHandler(HttpServletRequest req, BizException e) {log.error("发生业务异常: {}, 请求接口: {}", e.getMessage(), req.getRequestURI());return ReturnResult.error(e.getCode(), e.getMessage());}@ExceptionHandler(value = NullPointerException.class)@ResponseBodypublic ReturnResult exceptionHandler(HttpServletRequest req, NullPointerException e) {log.error("空指针异常信息: {}, 请求接口: {}", e, req.getRequestURI());return ReturnResult.error(NULL_POINT_ERROR_EXCEPTION.getCode(),NULL_POINT_ERROR_EXCEPTION.getMessage()+ RIGHT_PARENTHESES+ e.getMessage()+ LEFT_PARENTHESES);}@ExceptionHandler(value = HttpRequestMethodNotSupportedException.class)@ResponseBodypublic ReturnResult methodNotSupportedExceptionHandler(HttpServletRequest req, Exception e) {log.error("请求方法异常信息: {}，请求接口: {}", e, req.getRequestURI());return ReturnResult.error(REQUEST_METHOD_ERROR.getCode(),REQUEST_METHOD_ERROR.getMessage() + RIGHT_PARENTHESES + e.getMessage() + LEFT_PARENTHESES);}@ExceptionHandler(value = MyBatisSystemException.class)@ResponseBodypublic ReturnResult sqlSyntaxErrorExceptionHandler(HttpServletRequest req, Exception e) {log.error("MyBatis系统异常信息: {}，请求接口: {}", e, req.getRequestURI());return ReturnResult.error(INNER_FRAME_EXCEPTION.getCode(),INNER_FRAME_EXCEPTION.getMessage() + RIGHT_PARENTHESES + e.getMessage() + LEFT_PARENTHESES);}@ExceptionHandler(value = AuthenticationException.class)public ReturnResult incorrectCredentialsException(HttpServletRequest request, AuthenticationException e) {log.error("用户名或密码不正确: {}, 请求接口: {}", e, request.getRequestURI());return ReturnResult.error(USER_CREDENTIALS_ERROR);}@ExceptionHandler(value = UserException.class)public ReturnResult incorrectUserException(HttpServletRequest request, UserException e) {log.error("用户信息异常: {}, 请求接口: {}", e, request.getRequestURI());return ReturnResult.error(e.getCode(), e.getMessage());}@ExceptionHandler(value = Exception.class)@ResponseBodypublic ReturnResult exceptionHandler(HttpServletRequest req, Exception e) {e.printStackTrace();log.error("未知异常: {}, 请求接口: {}", e, req.getRequestURI());return ReturnResult.error(INTERNAL_SERVER_ERROR.getCode(),INTERNAL_SERVER_ERROR.getMessage() + RIGHT_PARENTHESES + e.getMessage() + LEFT_PARENTHESES);}
}

2.2 自定义业务异常类

import com.sugon.cloud.lowcode.result.BaseResultInterface;
import com.sugon.cloud.lowcode.result.CodeMessageEnum;
import io.swagger.annotations.ApiModel;
import io.swagger.annotations.ApiModelProperty;@ApiModel(description= "业务异常数据")
public class BizException extends RuntimeException implements BaseResultInterface {private static final long serialVersionUID = 1L;@ApiModelProperty(value = "错误码")private String code;@ApiModelProperty(value = "错误信息")private String message;public BizException() {super();}public BizException(CodeMessageEnum codeMessageEnum) {super(codeMessageEnum.getCode());this.code = codeMessageEnum.getCode();this.message = codeMessageEnum.getMessage();}public BizException(CodeMessageEnum codeMessageEnum, Throwable cause) {super(codeMessageEnum.getCode(), cause);this.code = codeMessageEnum.getCode();this.message = codeMessageEnum.getMessage();}public BizException(CodeMessageEnum codeMessageEnum, String message, Throwable cause) {super(codeMessageEnum.getCode(), cause);this.code = codeMessageEnum.getCode();this.message = message;}public BizException(String message) {super(message);this.message = message;}public BizException(String code, String message) {super(code);this.code = code;this.message = message;}public BizException(String code, String message, Throwable cause) {super(code, cause);this.code = code;this.message = message;}@Overridepublic Throwable fillInStackTrace() {return this;}@Overridepublic String getCode() {return this.code;}@Overridepublic String getMessage() {return this.message;}
}

3. 统一返回格式

在上述代码中，所有的异常处理方法返回的是ReturnResult对象，它封装了返回给前端的数据。ReturnResult类的设计使得前端可以统一解析和展示错误信息。

3.1 返回结果类

import com.alibaba.fastjson.JSONObject;
import io.swagger.annotations.ApiModel;
import io.swagger.annotations.ApiModelProperty;
import lombok.Getter;
import lombok.Setter;import static com.sugon.cloud.lowcode.result.CodeMessageEnum.*;@Setter
@Getter
@ApiModel(description= "返回响应数据")
public class ReturnResult<T> {@ApiModelProperty(value = "状态码")private String code;@ApiModelProperty(value = "响应信息")private String message;@ApiModelProperty(value = "响应对象")private T result;@ApiModelProperty(value = "是否成功")private boolean success = true;public ReturnResult() {}public ReturnResult(CodeMessageEnum codeMessageEnum) {this.code = codeMessageEnum.getCode();this.message = codeMessageEnum.getMessage();}public static ReturnResult success() {return success(null);}public static <T> ReturnResult<T> success(T data) {return success(SUCCESS, data);}public static <T> ReturnResult<T> loginSuccess(T data) {return success(SUCCESS_LOGIN, data);}public static ReturnResult loginOutSuccess() {return success(SUCCESS_LOGOUT, null);}private static <T> ReturnResult<T> success(CodeMessageEnum codeMessageEnum, T data) {ReturnResult<T> result = new ReturnResult<>();result.setCode(codeMessageEnum.getCode());result.setMessage(codeMessageEnum.getMessage());result.setResult(data);return result;}public static ReturnResult error(CodeMessageEnum codeMessageEnum) {return error(codeMessageEnum.getCode(), codeMessageEnum.getMessage());}public static ReturnResult error(CodeMessageEnum codeMessageEnum, String message) {return error(codeMessageEnum.getCode(), message);}public static ReturnResult error(String code, String message) {ReturnResult result = new ReturnResult();result.setCode(code);result.setMessage(message);result.setSuccess(false);return result;}@Overridepublic String toString() {return JSONObject.toJSONString(this);}
}

4. 总结

通过@RestControllerAdvice和@ExceptionHandler，我们可以在Spring Boot应用中实现全局异常处理，统一管理和处理所有异常。这样不仅可以

减少重复代码，还能使代码更加整洁，提高可维护性。同时，通过统一的返回格式，前端处理响应数据时也能更加方便。

希望这篇文章对您在Spring Boot中实现全局异常处理有所帮助。如有任何问题或建议，欢迎交流探讨。