Java秒杀系统---1.使用Result<>向前端传递数据

1.使用Result<T>类来封装发送给前端的数据

　　Result<T>类功能：封装需要向前端传递的数据。

　　Result<T>类的内部构造：在内部封装三个元素，code，msg，T  data；和两个构造方法，一个用来传递成功信息，另一个用来传递失败信息。

 1 package com.app.miaosha.Result;
 2
 3 import lombok.Data;
 4
 5 @Data
 6 public class Result<T> {
 7     private int code;
 8     private String msg;
 9     private T data;
10
11
12     private Result(T data){
13         this.code=0;
14         this.msg="success";
15         this.data=data;
16     }
17
18     private Result(CodeMsg msg){
19         if (msg == null) {
20             return;
21         }
22         this.code = msg.getCode();
23         this.msg = msg.getMsg();
24     }
25
26
27     public static <T> Result<T> success(T data) {
28         return new Result<T>(data);
29     }
30     public static <T> Result<T> error(CodeMsg codeMsg){
31         return new Result<T>(codeMsg);
32     }
33
34 }

2.失败信息的封装类CodeMsg

　　为方便用户传输失败信息而建立。包括两个参数：code，message。

package com.app.miaosha.Result;

import lombok.Data;

@Data
public class CodeMsg {
    private int code;
    private String msg;

    //通用异常
    public static CodeMsg SERVER_ERROR = new CodeMsg(500100, "服务端异常！");
    public static CodeMsg BIND_ERROR = new CodeMsg(500101, "参数校验异常：%s!");
    public static CodeMsg REQUEST_ILLEGAL = new CodeMsg(500102, "请求非法！");
    public static CodeMsg ACCESS_LIMIT_REACHED = new CodeMsg(500103, "访问太频繁！");

    //登录模块 5002XX
    public static CodeMsg SESSION_ERROR = new CodeMsg(500210, "Session不存在或者已经失效！");
    public static CodeMsg PASSWORD_EMPTY = new CodeMsg(500211, "登录密码不能为空！");
    public static CodeMsg MOBILE_EMPTY = new CodeMsg(500212, "手机号码不能为空！");
    public static CodeMsg MOBILE_ERROR = new CodeMsg(500213, "手机号码格式错误！");
    public static CodeMsg MOBILE_NOT_EXIST = new CodeMsg(500214, "用户不存在！");
    public static CodeMsg PASSWORD_ERROR = new CodeMsg(500215, "密码错误！");
    public static CodeMsg USER_NO_LOGIN = new CodeMsg(500216, "用户未登录！");

    //订单模块 5004XX
    public static CodeMsg ORDER_NOT_EXIST = new CodeMsg(500400, "订单不存在！");

    //秒杀模块 5005XX
    public static CodeMsg SECKILL_OVER = new CodeMsg(500500, "商品已经秒杀完毕！");
    public static CodeMsg REPEATE_SECKILL = new CodeMsg(500501, "不能重复秒杀！");
    public static CodeMsg SECKILL_FAIL = new CodeMsg(500502, "秒杀失败！");

    private CodeMsg(int code, String msg) {
        this.code = code;
        this.msg = msg;
    }

    @Override
    public String toString() {
        return "CodeMsg{" +
                "code=" + code +
                ", msg=‘" + msg + ‘\‘‘ +
                ‘}‘;
    }
}

原文地址：https://www.cnblogs.com/deijiawoyu/p/12662599.html