1、首先创建测试代码实体类，用于解析json数据之后存放数据的实体类，年级Grade类
private String course;//课程字段
private String score;//分数字段
2、再创建一个学生实体类，Student类
private String name;//学生名字
private int age;//年纪
private String sex;//性别
private Grade grade;//年级
3、创建TestGson测试类，添加一个main方法，作为测试入口
4、首先解析单条无嵌套Json数据的
String jsonStr = "{'name':'Tom', 'age':30, 'sex':'male'}";
Gson gson = new Gson();
Student student = gson.fromJson(jsonStr, Student.class);
System.out.println(student);
运行查看结果
5、//解析单条有嵌套的Json数据
String jsonStr1 = "{'name':'Tom', 'age':30, 'sex':'male', 'grade':{'course':'java','score':'100'}}";
Gson gson1 = new Gson();
Student student1 = gson1.fromJson(jsonStr1, Student.class);
System.out.println(student1);
6、//解析Json数组
String jsonStr2 = "[{'name':'Tom', 'age':30, 'sex':'male', 'grade':{'course':'java','score':'100'}}," +
"{'name':'Lili', 'age':25, 'sex':'female', 'grade':{'course':'java','score':'100'}}]";
Gson gson2 = new Gson();
List<Student> students = gson2.fromJson(jsonStr2, new TypeToken<List<Student>>(){}.getType());
System.out.println(students);
