不要再满屏写 try...catch 了！这个更香！

来源：www.toutiao.com/i6878184496945070604

# 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 *  */@RestControllerAdvicepublic 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：