利用Gson转换Json实例

    import java.util.ArrayList;  
    import java.util.Date;  
    import java.util.List;  
      
    import com.google.gson.Gson;  
    import com.google.gson.reflect.TypeToken;  
      
    public class GsonTest1 {  
      
        public static void main(String[] args) {  
            Gson gson = new Gson();  
      
            Student student1 = new Student();  
            student1.setId(1);  
            student1.setName("李坤");  
            student1.setBirthDay(new Date());  
      
            // //  
            System.out.println("----------简单对象之间的转化-------------");  
            // 简单的bean转为json  
            String s1 = gson.toJson(student1);  
            System.out.println("简单Bean转化为Json===" + s1);  
      
            // json转为简单Bean  
            Student student = gson.fromJson(s1, Student.class);  
            System.out.println("Json转为简单Bean===" + student);  
            // 结果:  
            // 简单Bean转化为Json==={"id":1,"name":"李坤","birthDay":"Jun 22, 2012 8:27:52 AM"}  
            // Json转为简单Bean===Student [birthDay=Fri Jun 22 08:27:52 CST 2012, id=1,  
            // name=李坤]  
            // //  
      
            Student student2 = new Student();  
            student2.setId(2);  
            student2.setName("曹贵生");  
            student2.setBirthDay(new Date());  
      
            Student student3 = new Student();  
            student3.setId(3);  
            student3.setName("柳波");  
            student3.setBirthDay(new Date());  
      
            List<Student> list = new ArrayList<Student>();  
            list.add(student1);  
            list.add(student2);  
            list.add(student3);  
      
            System.out.println("----------带泛型的List之间的转化-------------");  
            // 带泛型的list转化为json  
            String s2 = gson.toJson(list);  
            System.out.println("带泛型的list转化为json==" + s2);  
      
            // json转为带泛型的list  
            List<Student> retList = gson.fromJson(s2,  
                    new TypeToken<List<Student>>() {  
                    }.getType());  
            for (Student stu : retList) {  
                System.out.println(stu);  
            }  
      
       
执行结果:

    ----------简单对象之间的转化-------------  
    简单Bean转化为Json==={"id":1,"name":"李坤","birthDay":"Jun 22, 2012 9:10:31 PM"}  
    Json转为简单Bean===Student [birthDay=Fri Jun 22 21:10:31 CST 2012, id=1, name=李坤]  
    ----------带泛型的List之间的转化-------------  

    带泛型的list转化为json==[{"id":1,"name":"李坤","birthDay":"Jun 22, 2012 9:10:31 PM"},

                                                  {"id":2,"name":"曹贵生","birthDay":"Jun 22, 2012 9:10:31 PM"},

                                                  {"id":3,"name":"柳波","birthDay":"Jun 22, 2012 9:10:31 PM"}]
    Student [birthDay=Fri Jun 22 21:10:31 CST 2012, id=1, name=李坤]  
    Student [birthDay=Fri Jun 22 21:10:31 CST 2012, id=2, name=曹贵生]  
    Student [birthDay=Fri Jun 22 21:10:31 CST 2012, id=3, name=柳波]