可以通过Gson使用两种方法，将json字符串转换为对象，以下面该段报文做测试
{ ???"id": 84041462, ???"lastName": "小华", ???"age":32, ???"balance":666255.32, ???"hobbyDesc": { ???????"subject": "数学", ???????"score":25, ???????"sport_desc":"跑步有益健康" ???} ???}1. 创建实体类，通过 fromJson方法将json数据封装进对象中
如上，将上面报文按层次解析并创建两个对象
import com.google.gson.annotations.SerializedName;public class HobbyDesc { ???private String subject; ???private int score; ???@SerializedName("sport_desc") ???private String sportDesc; ???//***public class Account { ???private String id; ???private String lastName; ???private int age; ???private double balance; ???private HobbyDesc hobbyDesc; ???
???//***解析
String jsonStr = "{\n" + ???????????????"\t\"id\": 84041462,\n" + ???????????????"\t\"lastName\": \"小华\",\n" + ???????????????"\t\"age\":32,\n" + ???????????????"\t\"balance\":666255.32,\n" + ???????????????"\t\"hobbyDesc\": {\n" + ???????????????"\t\t\"subject\": \"数学\",\n" + ???????????????"\t\t\"score\":25,\n" + ???????????????"\t\t\"sport_desc\":\"跑步有益健康\"\n" + ???????????????"\t}\n" + ???????????????"\t\n" + ???????????????"}";Account account = new Gson().fromJson(jsonStr,Account.class);同时也可以看到，对象中定义为字符串类型的字段也可以接受json串的数值类型，没有转换问题。
2. 解析为jsonObject对象
直接使用Gson API解析
String jsonStr = "{\n" + ???????????????"\t\"id\": 84041462,\n" + ???????????????"\t\"lastName\": \"小华\",\n" + ???????????????"\t\"age\":32,\n" + ???????????????"\t\"balance\":666255.32,\n" + ???????????????"\t\"hobbyDesc\": {\n" + ???????????????"\t\t\"subject\": \"数学\",\n" + ???????????????"\t\t\"score\":25,\n" + ???????????????"\t\t\"sport_desc\":\"跑步有益健康\"\n" + ???????????????"\t}\n" + ???????????????"\t\n" + ???????????????"}";JsonObject jsonObject = (JsonObject) new JsonParser().parse(jsonStr);
???System.out.println("id <getAsInt> = "+jsonObject.get("id").getAsInt());//id <getAsInt> = 84041462System.out.println("id <getAsString> = "+jsonObject.get("id").getAsString());//id <getAsString> = 84041462System.out.println("position = "+ jsonObject.get("hobbyDesc").getAsJsonObject().get("sport_desc").getAsString());//position = 跑步有益健康参照jsonObject结构，可以了解Gson这种封装对象的方式，如果仅仅是取某值的话，可以采用这种方式，可以节约大量时间
Gson转换json数据为对象
原文地址：https://www.cnblogs.com/zjfjava/p/10122327.html