自定义结果类

1. 自定义结果类
   参考：https://www.jianshu.com/p/398bf406f8e6
   参考：https://blog.csdn.net/zhang150114/article/details/90477002
   参考：https://zhuanlan.zhihu.com/p/414255238
   参考：https://blog.csdn.net/dedede001/article/details/128267515

2. 示例代码

// ResponseResult类
@Data
@NoArgsConstructor
public class ResponseResult<T> implements Serializable {

    //
    private Integer code;
    private String msg;
    private T data;

    // 成功-数据
    public static <T> ResponseResult<T> ok(T data) {
        return build(data, ResultEnum.SUCCESS);
    }

    // 成功--空参
    public static <T> ResponseResult<T> ok() {
        return ok(null);
    }

    // 成功--数据和提示信息
    public static <T> ResponseResult<T> ok(String msg,T data) {
        ResponseResult<T> result = ok(data);
        result.setMsg(msg);
        return result;
    }

    // 成功--提示信息
    public static <T> ResponseResult<T> ok(String msg) {
        ResponseResult<T> result = ok();
        result.setMsg(msg);
        return result;
    }

    // 失败--传枚举
    public static <T> ResponseResult<T> fail(ResultEnum resultEnum) {
        return build(null, resultEnum);
    }

    // 失败--什么也不传
    public static <T> ResponseResult<T> fail() {
        return build(null, ResultEnum.FAIL);
    }

    // 失败--传数据和枚举
    public static <T> ResponseResult<T> fail(T data, ResultEnum resultEnum) {
        return build(data, resultEnum);
    }



    // 构造数据--传所有变量
    public static <T> ResponseResult<T> build(Integer code, String msg, T data) {
        ResponseResult<T> result = build(data);
        result.setMsg(msg);
        result.setCode(code);
        return result;
    }

    // 构造数据--只传数据
    public static <T> ResponseResult<T> build(T data) {
        ResponseResult<T> responseResult = new ResponseResult<>();
        if (data != null) {
            responseResult.setData(data);
        }
        return responseResult;
    }

    // 构造数据--传数据和枚举值
    public static <T> ResponseResult<T> build(T data, ResultEnum resultEnum) {
        ResponseResult<T> responseResult = build(data);
        responseResult.setCode(resultEnum.getCode());
        responseResult.setMsg(resultEnum.getMsg());
        return responseResult;
    }
}

// 枚举类
public enum AppHttpCodeEnum {

    // 成功段固定为200
    SUCCESS(200,"操作成功"),
    // 登录段1~50
    NEED_LOGIN(1,"需要登录后操作"),
    LOGIN_PASSWORD_ERROR(2,"密码错误"),
    // TOKEN50~100
    TOKEN_INVALID(50,"无效的TOKEN"),
    TOKEN_EXPIRE(51,"TOKEN已过期"),
    TOKEN_REQUIRE(52,"TOKEN是必须的"),
    // SIGN验签 100~120
    SIGN_INVALID(100,"无效的SIGN"),
    SIG_TIMEOUT(101,"SIGN已过期"),
    // 参数错误 500~1000
    PARAM_REQUIRE(500,"缺少参数"),
    PARAM_INVALID(501,"无效参数"),
    PARAM_IMAGE_FORMAT_ERROR(502,"图片格式有误"),
    SERVER_ERROR(503,"服务器内部错误"),
    // 数据错误 1000~2000
    DATA_EXIST(1000,"数据已经存在"),
    AP_USER_DATA_NOT_EXIST(1001,"ApUser数据不存在"),
    DATA_NOT_EXIST(1002,"数据不存在"),
    // 数据错误 3000~3500
    NO_OPERATOR_AUTH(3000,"无权限操作"),
    NEED_ADMIND(3001,"需要管理员权限"),

    // 自媒体文章错误 3501~3600
    MATERIASL_REFERENCE_FAIL(3501,"素材引用失效");


    int code;
    String errorMessage;

    AppHttpCodeEnum(int code, String errorMessage){
        this.code = code;
        this.errorMessage = errorMessage;
    }

    public int getCode() {
        return code;
    }

    public String getErrorMessage() {
        return errorMessage;
    }
}