Json转换利器Gson之实例一-简单对象转化和带泛型的List转化

ITprivate

2014-03-04

Gson 是 Google 提供的用来在 Java 对象和 JSON 数据之间进行映射的 Java 类库。可以将一个 JSON 字符串转成一个 Java 对象，或者反过来。

jar和源码下载地址: http://code.google.com/p/google-gson/downloads/list

实体类:

public class Student {  
    private int id;  
    private String name;  
    private Date birthDay;  
  
    public int getId() {  
        return id;  
    }  
  
    public void setId(int id) {  
        this.id = id;  
    }  
  
    public String getName() {  
        return name;  
    }  
  
    public void setName(String name) {  
        this.name = name;  
    }  
  
    public Date getBirthDay() {  
        return birthDay;  
    }  
  
    public void setBirthDay(Date birthDay) {  
        this.birthDay = birthDay;  
    }  
  
    @Override  
    public String toString() {  
        return "Student [birthDay=" + birthDay + ", id=" + id + ", name="  
                + name + "]";  
    }  
  
}

测试类:

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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);
}
// 结果:
// 带泛型的list转化为json== [{"id":1,"name":"李坤","birthDay":"Jun 22, 2012 8:28:52 AM"}, {"id":2,"name":"曹贵生","birthDay":"Jun 22, 2012 8:28:52 AM"}, {"id":3,"name":"柳波","birthDay":"Jun 22, 2012 8:28:52 AM"}]
// Student [birthDay=Fri Jun 22 08:28:52 CST 2012, id=1, name=李坤]
// Student [birthDay=Fri Jun 22 08:28:52 CST 2012, id=2, name=曹贵生]
// Student [birthDay=Fri Jun 22 08:28:52 CST 2012, id=3, name=柳波]
}
}

执行结果:

[plain] view plain copy

----------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]

Json转换利器Gson之实例一-简单对象转化和带泛型的List转化 (http://blog.csdn.net/lk_blog/article/details/7685169)
Json转换利器Gson之实例二-Gson注解和GsonBuilder (http://blog.csdn.net/lk_blog/article/details/7685190)
Json转换利器Gson之实例三-Map处理(上) (http://blog.csdn.net/lk_blog/article/details/7685210)
Json转换利器Gson之实例四-Map处理(下) (http://blog.csdn.net/lk_blog/article/details/7685224)
Json转换利器Gson之实例五-实际开发中的特殊需求处理 (http://blog.csdn.net/lk_blog/article/details/7685237)
Json转换利器Gson之实例六-注册TypeAdapter及处理Enum类型 (http://blog.csdn.net/lk_blog/article/details/7685347)

实例代码下载: http://download.csdn.net/detail/lk_blog/4387822

gson 泛型 list