Android中使用Google的GSON框架解析JSON数据----方便快捷(含代码)
什么是JSON:
JSON即JavaScript Object Natation, 它是一种轻量级的数据交换格式, 与XML一样, 是广泛被采用的客户端和服务端交互的解决方案.
JSON对象:
JSON中对象(Object)以"{"开始, 以"}"结束. 对象中的每一个item都是一个key-value对, 表现为"key:value"的形式, key-value对之间使用逗号分隔. 如:{"name":"coolxing", "age"=24, "male":true, "address":{"street":"huiLongGuan", "city":"beijing", "country":"china"}}. JSON对象的key只能是string类型的, 而value可以是string, number, false, true, null, Object对象甚至是array数组, 也就是说可以存在嵌套的情况.
JSON数组:
JSON数组(array)以"["开始, 以"]"结束, 数组中的每一个元素可以是string, number, false, true, null, Object对象甚至是array数组, 数组间的元素使用逗号分隔. 如["coolxing", 24, {"street":"huiLongGuan", "city":"beijing", "country":"china"}].
JSON数据的解析:
解析JSON数据, 首先需要明确待解析的是JSON Object还是JSON array, 然后需要确定采用哪种解析技术. android平台上一般有2种解析技术可供选择:android内置的org.json包和google的开源gson库. 以下将分别采用这两种技术解析JSON对象和JSON数组.
1. 采用android内置的org.json包解析JSON对象. 假设待解析的JSON数据为json = "{\"name\":\"coolxing\", \"age\"=24, \"male\":true, \"address\":{\"street\":\"huiLongGuan\", \"city\":\"beijing\", \"country\":\"china\"}}", 其中\用于转义表达式中的双引号. 首先定义2个JavaBean:
[java]
package text.com.bean;
public class Address {
private String street;
private String city;
private String country;
public Address() {
super();
}
public Address(String street, String city, String country) {
super();
this.street = street;
this.city = city;
this.country = country;
}
public String getStreet() {
return street;
}
public void setStreet(String street) {
this.street = street;
}
public String getCity() {
return city;
}
public void setCity(String city) {
this.city = city;
}
public String getCountry() {
return country;
}
public void setCountry(String country) {
this.country = country;
}
@Override
public String toString() {
return "Address [street=" + street + ", city=" + city + ", country="
+ country + "]";
}
}
[java]
package text.com.bean;
public class Person {
private String name;
private int age;
private boolean male;
private Address address;
public Person() {
super();
}
public Person(String name, int age, boolean male, Address address) {
super();
this.name = name;
this.age = age;
this.male = male;
this.address = address;
}
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 boolean isMale() {
return male;
}
public void setMale(boolean male) {
this.male = male;
}
public Address getAddress() {
return address;
}
public void setAddress(Address address) {
this.address = address;
}
@Override
public String toString() {
return "Person [name=" + name + ", age=" + age + ", male=" + male
+ ", address=" + address + "]";
}
}
首先使用方法一解析代码如下:
[java]
JSONObject jsonObject = new JSONObject(json);
String name = jsonObject.getString("name");
int age = jsonObject.getInt("age");
boolean male = jsonObject.getBoolean("male");
JSONObject addressJSON = jsonObject.getJSONObject("address");
String street = addressJSON.getString("street");
String city = addressJSON.getString("city");
String country = addressJSON.getString("country");
Address address = new Address(street, city, country);
Person person = new Person(name, age, male, address);
System.out.println(person);