java中json转换成string类型_java中String转换成json json转换成String

前置添加pom

com.google.code.gson

gson

2.2.4

1、json转换成String

import com.google.gson.Gson;

import com.google.gson.GsonBuilder;

class JsonUtil{

public static StringobjectToJsonString(Object obj) {

return createGsonSetDateFormat("yyyy-MM-dd HH:mm:ss").toJson(obj);

}

private static GsoncreateGsonSetDateFormat(String dateFormat) {

return (new GsonBuilder()).setDateFormat(dateFormat).create();

}

}

2、String(json)转换成json Gson gson = new Gson();

Map map = new HashMap();

map = gson.fromJson(value, map.getClass());

System.out.println(map.toString());

String goodsid=(String) map.get("event");

System.out.println("map的值为:"+goodsid);