Android 编程下使用 Google 的 Gson 解析 Json

Gson 使用示例

package cn.sunzn.gson;

import java.util.ArrayList;
import java.util.Collections;
import java.util.List;

import android.app.Activity;
import android.os.Bundle;
import android.util.Log;
import cn.sunzn.bean.Person;

import com.google.gson.Gson;
import com.google.gson.reflect.TypeToken;

public class GsonActivity extends Activity {

    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        
        Gson gson = new Gson();

        /**
         * 将给定的 JSON 字符串转换成指定的类型对象
         */
        String json = "{"name":"Tom","age":90}";
        Person person = gson.fromJson(json, Person.class);
        Log.e("GSON", person.toString());

        /**
         * 将给定的目标对象转换成 JSON 格式的字符串
         */
        String json_Person = gson.toJson(person);
        Log.e("GSON", json_Person);

        /**
         * 将给定的集合对象转换成 JSON 格式的字符串
         */
        ArrayList<Person> persons = new ArrayList<Person>();
        Collections.addAll(persons, new Person("tom", 10), new Person("jon", 20));
        String json_list = gson.toJson(persons);
        Log.e("GSON", json_list);

        /**
         * 将给定的 JSON 格式字符串转换为带泛型的集合对象
         */
        List<Person> retList = gson.fromJson(json_list, new TypeToken<List<Person>>() {}.getType());
        for (Person p : retList) {
            Log.e("GSON", p.toString());
        }
    }
}

Gson 解析 Json 运行结果

02-19 07:39:23.467: E/GSON(669): Person [name=Tom, age=90]
02-19 07:39:23.487: E/GSON(669): {"name":"Tom","age":90}
02-19 07:39:23.517: E/GSON(669): [{"name":"tom","age":10},{"name":"jon","age":20}]
02-19 07:39:23.547: E/GSON(669): Person [name=tom, age=10]
02-19 07:39:23.547: E/GSON(669): Person [name=jon, age=20]

Gson 转换过程中使用的实体类 Person

package cn.sunzn.bean;

import com.google.gson.annotations.Expose;

public class Person {
    @Expose
    private String name;
    @Expose
    private int age;

    public Person() {
        super();
    }

    public Person(String name, int age) {
        super();
        this.name = name;
        this.age = age;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public int getAge() {
        return age;
    }

    public void setAge(int age) {
        this.age = age;
    }

    public String toString() {
        return "Person [name=" + name + ", age=" + age + "]";
    }

}

Gson 演示源码下载：Gson