java map 转 json 自编封装

1、自编封装代码：

import com.alibaba.fastjson.JSON;
import java.util.*;

public class jsonConversion {

    private String conversion(Map<String, String> data){

          StringBuilder str = new StringBuilder("{");

         for (String key : data.keySet()) {

             str.append(""").append(key).append(""").append(":").append(""").append(data.get(key)).append(""").append(",");
         }
         str.append("}");
        return str.toString();

     }

    public static void main(String[] args){
        Map<String, String> map = new HashMap<>();
        map.put("name", "bb");
        map.put("age", "cc");
        map.put("good", "123");
        
        jsonConversion jsoncon = new jsonConversion();
        String json = jsoncon.conversion(map);
        System.out.println(json);
        Map maps = (Map) JSON.parse(json);
        System.out.println(maps.get("name"));
    }
}