减少 try...catch，定义全局统一异常处理器！

前言

软件开发springboot项目过程中，不可避免的需要处理各种异常,spring mvc 架构中各层会出现大量的try {...} catch {...} finally {...}代码块，不仅有大量的冗余代码，而且还影响代码的可读性。这样就需要定义个全局统一异常处理器，以便业务层再也不必处理异常。

推荐理由

• 代码复制到项目中通过简单的配置即可实现

• 可以灵活的根据自己的业务异常进行更细粒度的扩展

实践

1 封装统一返回结果类

源代码

public class AjaxResult {//是否成功private Boolean success;//状态码private Integer code;//提示信息private String msg;//数据private Object data;public AjaxResult() {}//自定义返回结果的构造方法public AjaxResult(Boolean success,Integer code, String msg,Object data) {this.success = success;this.code = code;this.msg = msg;this.data = data;}//自定义异常返回的结果public static AjaxResult defineError(BusinessException de){AjaxResult result = new AjaxResult();result.setSuccess(false);result.setCode(de.getErrorCode());result.setMsg(de.getErrorMsg());result.setData(null);return result;}//其他异常处理方法返回的结果public static AjaxResult otherError(ErrorEnum errorEnum){AjaxResult result = new AjaxResult();result.setMsg(errorEnum.getErrorMsg());result.setCode(errorEnum.getErrorCode());result.setSuccess(false);result.setData(null);return result;}public Boolean getSuccess() {return success;}public void setSuccess(Boolean success) {this.success = success;}public Integer getCode() {return code;}public void setCode(Integer code) {this.code = code;}public String getMsg() {return msg;}public void setMsg(String msg) {this.msg = msg;}public Object getData() {return data;}public void setData(Object data) {this.data = data;}}

2 自定义异常封装类

源码：

public class BusinessException extends RuntimeException {private static final long serialVersionUID = 1L;/*** 错误状态码*/protected Integer errorCode;/*** 错误提示*/protected String errorMsg;public BusinessException(){}public BusinessException(Integer errorCode, String errorMsg) {this.errorCode = errorCode;this.errorMsg = errorMsg;}public Integer getErrorCode() {return errorCode;}public void setErrorCode(Integer errorCode) {this.errorCode = errorCode;}public String getErrorMsg() {return errorMsg;}public void setErrorMsg(String errorMsg) {this.errorMsg = errorMsg;}
}

3 错误枚举，拒绝硬编码

源码

public enum ErrorEnum {// 数据操作错误定义SUCCESS(200, "成功"),NO_PERMISSION(403,"你没得权限"),NO_AUTH(401,"未登录"),NOT_FOUND(404, "未找到该资源!"),INTERNAL_SERVER_ERROR(500, "服务器异常请联系管理员"),;/** 错误码 */private Integer errorCode;/** 错误信息 */private String errorMsg;ErrorEnum(Integer errorCode, String errorMsg) {this.errorCode = errorCode;this.errorMsg = errorMsg;}public Integer getErrorCode() {return errorCode;}public String getErrorMsg() {return errorMsg;}
}

4 全局异常处理类

源码

/*** 全局异常处理器* */
@RestControllerAdvice
public class GlobalExceptionHandler
{private static final Logger log = LoggerFactory.getLogger(GlobalExceptionHandler.class);/*** 处理自定义异常**/@ExceptionHandler(value = BusinessException.class)public AjaxResult bizExceptionHandler(BusinessException e) {log.error(e.getMessage(), e);return AjaxResult.defineError(e);}/***处理其他异常**/@ExceptionHandler(value = Exception.class)public AjaxResult exceptionHandler( Exception e) {log.error(e.getMessage(), e);return AjaxResult.otherError(ErrorEnum.INTERNAL_SERVER_ERROR);}
}

5 测试

返回结果：