状态码类：

public enum ServiceCode {OK(20000),ERR_BAD_REQUEST(40000),//错误请求ERR_NOT_FOUND(40400),//没有发现ERR_UNAUTHORIZED(40100),//未经授权ERR_UNAUTHORIZED_DISABLED(40110),//未经授权禁止ERR_FORBIDDEN(40300),//被禁止的ERR_CONFLICT(40900),//冲突ERR_INSERT(50000),//插入异常ERR_DELETE(50100),//删除异常ERR_UPDATE(50200),//更新异常ERR_SELECT(50300),//搜索异常ERR_JWT_EXPIRED(60000),//jwt过期ERR_JWT_MALFORMED(60100),//jwt格式不对ERR_JWT_SIGNATURE(60200),//jwl签名错误ERR_UNKNOWN(99999);//未知错误private Integer value;ServiceCode(Integer value) {this.value = value;}public Integer getValue() {return value;}}

返回类：

/*** 统一的响应结果类型*/
@Data  //依赖导入lombok
public class JsonResult<T> implements Serializable {/*** 操作结果的状态码*/@ApiModelProperty("业务状态码")private Integer state;/*** 操作“失败”时响应的提示文本*/@ApiModelProperty("消息")private String message;/*** 操作“成功”时响应的数据*/@ApiModelProperty("数据")private T data; // T=Type, E=Element, K=Key, V=Value。泛型public static JsonResult<Void> ok() {return ok(null);}public static <T> JsonResult<T> ok(T data) {JsonResult jsonResult = new JsonResult();jsonResult.setState(ServiceCode.OK.getValue());jsonResult.setData(data);return jsonResult;}public static JsonResult<Void> fail(ServiceException e) {return fail(e.getServiceCode(), e.getMessage());}public static JsonResult<Void> fail(ServiceCode serviceCode, String message) {JsonResult jsonResult = new JsonResult();jsonResult.setState(serviceCode.getValue());jsonResult.setMessage(message);return jsonResult;}}public static JsonResult<Void> fail(ServiceException e) {return fail(e.getServiceCode(), e.getMessage());}public static JsonResult<Void> fail(ServiceCode serviceCode, String message) {JsonResult jsonResult = new JsonResult();jsonResult.setState(serviceCode.getValue());jsonResult.setMessage(message);return jsonResult;}}

（没有找到数据、不符合业务、查询失败等均抛出异常类，相当于if ···else···中的else情况）异常类：

/*** 业务异常*/
public class ServiceException extends RuntimeException {private ServiceCode serviceCode;public ServiceException(ServiceCode serviceCode, String message) {super(message);this.serviceCode = serviceCode;}public ServiceCode getServiceCode() {return serviceCode;}}

使用：

//成功情况，不带数据，只返回2000状态码public JsonResult<Void> 方法名(参数（可选）)               return JsonResult.ok();}//成功情况，带数据.T表示需要返回的数据类型，如：对象、list、string·····public JsonResult<T> 方法名(参数（可选）)               return  JsonResult.ok(T)}//错误情况，ServiceCode.状态码。message为字符串
JsonResult<Void> jsonResult = JsonResult.fail(ServiceCode.状态码, message);
return jsonResult;//或者抛异常
throw new ServiceException(ServiceCode.状态码, message);