GSON解析JSON数据

准备工作

GSON下载地址:http://download.csdn.net/detail/wiseclown/9496184

JavaBean(自定义):

public class Student {

    private String id;
    private String name;
    private String sex;

    public String getName() {
        return name;
    }

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

    public String getId() {
        return id;
    }

    public void setId(String id) {
        this.id = id;
    }

    public String getSex() {
        return sex;
    }

    public void setSex(String sex) {
        this.sex = sex;
    }
}

读JSON数据

//单个对象
String json = "{\"id\":\"0001\",\"name\":\"zs\",\"sex\":\"male\"}";
Gson gson = new Gson();
Student student = gson.fromJson(json,Student.class);

//多个对象json数组
String json = "[{\"id\":\"0001\",\"name\":\"zs\",\"sex\":\"male\"}, {\"id\":\"0002\",\"name\":\"ls\",\"sex\":\"male\"}]";
Gson gson = new Gson();
List<Student> studentList = gson.fromJson(json,new TypeToken<List<Student>)(){}.getType();

从文件中读取JSON数据

student2.json
[{“id”:”000001”,”name”:”wz”,”sex”:”male”},
 {“id”:”000002”,”name”:”zs”,”sex”:”male”},
 {“id”:”000003”,”name”:”wf”,”sex”:”female”}
]

File file = new File(Environment.getExternalStorageDirectory(),"student2.json");
Gson gson = new Gson();
try{
    List<Student> studentList = gson.fromJson(new  
    InputStreamReader(new FileInputStream(file)),new   
    TypeToken<List<Student>(){}.getType());
}catch(FileNotFoundException e){
    e.printStackTrace();
}

将JSON数据写入文件中

Student student = new Student();
student.setId("1");
student.setName("wz");
student.setSex("male");
Gson gson = new Gson();
String jsonStr = gson.toJson(student);

File file = new File(Environment.getExternalStorageDirectory(),"student.json");
try{
      FileOutputStream out = new FileOutputStream(file);
      out.write(jsonStr.getBytes("UTF-8"));
} catch (FileNotFoundException e) {
      e.printStackTrace();
} catch (IOException e) {
      e.printStackTrace();
}