一

package com.ys.admin.util.result;

import lombok.Data;
import javax.servlet.http.HttpServletResponse;
import java.io.Serializable;

/**
 * @author He Yu
 * @date 2020/8/21 11:26
 */

@Data
public class R<T> implements Serializable {

    // 状态码
    private int code;
    // 是否成功
    private boolean success;
    // 承载数据
    private T data;
    // 返回消息
    private String msg;

    private R(IResultCode resultCode) {
        this(resultCode, null, resultCode.getMessage());
    }

    private R(IResultCode resultCode, String msg) {
        this(resultCode, null, msg);
    }

    private R(IResultCode resultCode, T data) {
        this(resultCode, data, resultCode.getMessage());
    }

    private R(IResultCode resultCode, T data, String msg) {
        this(resultCode.getCode(), data, msg);
    }

    private R(int code, T data, String msg) {
        this.code = code;
        this.data = data;
        this.msg = msg;
        this.success = ResultCode.SUCCESS.code == code;
    }



    /**
     * 返回R
     *
     * @param data 数据
     * @param <T>  T 泛型标记
     * @return R
     */
    public static <T> R<T> data(T data) {
        return data(data,null);
    }

    /**
     * 返回R
     *
     * @param data 数据
     * @param msg  消息
     * @param <T>  T 泛型标记
     * @return R
     */
    public static <T> R<T> data(T data, String msg) {
        return data(HttpServletResponse.SC_OK, data, msg);
    }

    /**
     * 返回R
     *
     * @param code 状态码
     * @param data 数据
     * @param msg  消息
     * @param <T>  T 泛型标记
     * @return R
     */
    public static <T> R<T> data(int code, T data, String msg) {
        return new R<>(code, data, msg);
    }

    /**
     * 返回R
     *
     * @param msg 消息
     * @param <T> T 泛型标记
     * @return R
     */
    public static <T> R<T> success(String msg) {
        return new R<>(ResultCode.SUCCESS, msg);
    }

    /**
     * 返回R
     *
     * @param resultCode 业务代码
     * @param <T>        T 泛型标记
     * @return R
     */
    public static <T> R<T> success(IResultCode resultCode) {
        return new R<>(resultCode);
    }

    /**
     * 返回R
     *
     * @param resultCode 业务代码
     * @param msg        消息
     * @param <T>        T 泛型标记
     * @return R
     */
    public static <T> R<T> success(IResultCode resultCode, String msg) {
        return new R<>(resultCode, msg);
    }

    /**
     * 返回R
     *
     * @param msg 消息
     * @param <T> T 泛型标记
     * @return R
     */
    public static <T> R<T> fail(String msg) {
        return new R<>(ResultCode.FAILURE, msg);
    }


    /**
     * 返回R
     *
     * @param code 状态码
     * @param msg  消息
     * @param <T>  T 泛型标记
     * @return R
     */
    public static <T> R<T> fail(int code, String msg) {
        return new R<>(code, null, msg);
    }

    /**
     * 返回R
     *
     * @param resultCode 业务代码
     * @param <T>        T 泛型标记
     * @return R
     */
    public static <T> R<T> fail(IResultCode resultCode) {
        return new R<>(resultCode);
    }

    /**
     * 返回R
     *
     * @param resultCode 业务代码
     * @param msg        消息
     * @param <T>        T 泛型标记
     * @return R
     */
    public static <T> R<T> fail(IResultCode resultCode, String msg) {
        return new R<>(resultCode, msg);
    }

}

二

package com.ys.admin.util.result;

import java.io.Serializable;

/**
 * @author He Yu
 * @date 2020/8/21 11:24
 */
public interface IResultCode extends Serializable {

    /**
     * 消息
     *
     * @return String
     */
    String getMessage();

    /**
     * 状态码
     *
     * @return int
     */
    int getCode();
}

三

package com.ys.admin.util.result;

import lombok.AllArgsConstructor;
import lombok.Getter;

import javax.servlet.http.HttpServletResponse;

/**
 * @author He Yu
 * @date 2020/8/21 11:34
 */
@Getter
@AllArgsConstructor
public enum  ResultCode implements IResultCode {

    /**
     * 操作成功
     */
    SUCCESS(HttpServletResponse.SC_OK, "操作成功"),

    /**
     * 业务异常
     */
    FAILURE(HttpServletResponse.SC_BAD_REQUEST, "业务异常"),

    /**
     * 请求未授权
     */
    UN_AUTHORIZED(HttpServletResponse.SC_UNAUTHORIZED, "请求未授权"),

    /**
     * 404 没找到请求
     */
    NOT_FOUND(HttpServletResponse.SC_NOT_FOUND, "404 没找到请求"),

    /**
     * 消息不能读取
     */
    MSG_NOT_READABLE(HttpServletResponse.SC_BAD_REQUEST, "消息不能读取"),

    /**
     * 不支持当前请求方法
     */
    METHOD_NOT_SUPPORTED(HttpServletResponse.SC_METHOD_NOT_ALLOWED, "不支持当前请求方法"),

    /**
     * 不支持当前媒体类型
     */
    MEDIA_TYPE_NOT_SUPPORTED(HttpServletResponse.SC_UNSUPPORTED_MEDIA_TYPE, "不支持当前媒体类型"),

    /**
     * 请求被拒绝
     */
    REQ_REJECT(HttpServletResponse.SC_FORBIDDEN, "请求被拒绝"),

    /**
     * 服务器异常
     */
    INTERNAL_SERVER_ERROR(HttpServletResponse.SC_INTERNAL_SERVER_ERROR, "服务器异常"),

    /**
     * 缺少必要的请求参数
     */
    PARAM_MISS(HttpServletResponse.SC_BAD_REQUEST, "缺少必要的请求参数"),

    /**
     * 请求参数类型错误
     */
    PARAM_TYPE_ERROR(HttpServletResponse.SC_BAD_REQUEST, "请求参数类型错误"),

    /**
     * 请求参数绑定错误
     */
    PARAM_BIND_ERROR(HttpServletResponse.SC_BAD_REQUEST, "请求参数绑定错误"),

    /**
     * 参数校验失败
     */
    PARAM_VALID_ERROR(HttpServletResponse.SC_BAD_REQUEST, "参数校验失败"),
    ;

    /**
     * code编码
     */
    final int code;
    /**
     * 中文信息描述
     */
    final String message;
}