java中(json)字符串、json、Map互转

// 前提：使用jar包为fastjson

import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.JSONObject;



// 程序如下:

Map map = new HashMap();
map.put("AAA", "1");
map.put("BBB", "2");
map.put("CCC", "3");
System.out.println("map=>"+map);

//1.map转string
String jsonString = JSON.toJSONString(map);
System.out.println("mapToString=>"+jsonString);
//2.map转jsonObject
JSONObject JSONObj = JSONObject.parseObject(JSON.toJSONString(map));
System.out.println("mapToJSON=>"+JSONObj);

//3.String转jsonObject
String jsonString2 = "{\"AAA\":\"1\",\"CCC\":\"3\",\"BBB\":\"2\"}";
JSONObject parseObject = JSONObject.parseObject(jsonString2);
System.out.println("StringToJson=>"+parseObject);
//4.String转map
Map stringToMap = JSONObject.parseObject(jsonString2);
System.out.println("StringToMap=>"+stringToMap);

String str = "{\"age\":\"24\",\"name\":\"summer\"}";
JSONObject jsonObject = JSONObject.parseObject(str);
//5.jsonObject转map
Map jsonToMap = JSONObject.parseObject(jsonObject.toJSONString());
System.out.println("jsonToMap=>"+jsonToMap);
//6.jsonObject转String
String jsonString3 = jsonObject.toJSONString();
System.out.println("jsonToString=>"+jsonString3);

 

 

 

结果如下

map=>{AAA=1, CCC=3, BBB=2}

mapToString=>{"AAA":"1","CCC":"3","BBB":"2"}

mapToJSON=>{"AAA":"1","CCC":"3","BBB":"2"}

StringToJson=>{"AAA":"1","CCC":"3","BBB":"2"}

StringToMap=>{"AAA":"1","CCC":"3","BBB":"2"}

jsonToMap=>{"name":"summer","age":"24"}

jsonToString=>{"name":"summer","age":"24"}