步骤:

1. 引用HTTP状态码库(非必选)
2. 新建封装类
3. 引用封装类

maven文件:

<dependency>
    <groupId>org.apache.httpcomponents</groupId>
    <artifactId>httpcore</artifactId>
    <version>4.4.13</version>
</dependency>

新建封装类:

package com.example.emos.wx.common.util;

import org.apache.http.HttpStatus;

import java.util.HashMap;
import java.util.Map;

public class R extends HashMap<String,Object> {
    public R(){
        put("code", HttpStatus.SC_OK);
        put("msg","success");
    }
    public R put(String key,Object value){
        super.put(key,value);
        return this;
    }
    public static R ok(){
        return new R();
    }
    public static R ok(String msg){
        R r=new R();
        r.put("msg",msg);
        return r;
    }
    public static R ok(Map<String,Object> map){
        R r=new R();
        r.putAll(map);
        return r;
    }

    public static R error(int code,String msg){
        R r=new R();
        r.put("code",code);
        r.put("msg",msg);
        return r;
    }
    public static R error(String msg){
        return error(HttpStatus.SC_INTERNAL_SERVER_ERROR,msg);
    }
    public static R error(){
        return error(HttpStatus.SC_INTERNAL_SERVER_ERROR,"未知异常，请联系管理员");
    }
}

controller文件:

return R.ok()
return R.ok("登陆成功")
return R.ok().put("name","GULAO")
return R.error("不能为空")