JSON：javaScript Object Notation
JSON數據是一系列鍵值對的集合
JSON Vs XML
1.JSON和XML的數據可讀性基本相同
2.JSON和XML同樣擁有豐富的解析手段
3.JSON相對於XML來講，數據的體積小
4.JSON與JavaScript的交互更加方便
5.JSON對數據的描述性比XML較差
Step:
Donwload google-gson-1.7.1-release.zip
uncompress the file
new folder libs for the project
copy gson- 1.7.1.java to libs
right key:Build path --> Add to build path
==================== <一> 解析一個JSON對象數組：===============================
JsonUtils.java
view plain
package lxy.litsoft;
import java.io.IOException;
import java.io.StringReader;
import android.util.Log;
import com.google.gson.stream.JsonReader;
public class JsonUtils {
public void parseJson(String jsonDate){
//如果需要解析JSON數據，首先要生成一個JsonReader對象
JsonReader reader = new JsonReader(new StringReader(jsonDate));
try {
//開始解析一個數組
reader.beginArray();
while(reader.hasNext()){ //判斷數組裏面有沒有下一個JSON對象
reader.beginObject(); //開始解析對象
while(reader.hasNext()){ //判斷是否有下一個鍵值對
String tagName = reader.nextName();
if(tagName.equals("name")){ //如果鍵爲"name"
Log.d("test", "name ---->"+reader.nextString());
} else if(tagName.equals("age")){ //如果鍵爲"age"
Log.d("test", "age ---->"+reader.nextInt());
}
}
reader.endObject(); //解析對象結束
}
reader.endArray(); //解析數組結束
} catch (IOException e) {
e.printStackTrace();
}
}
}
AppMain.java
view plain
package lxy.litsoft;
import android.app.Activity;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
public class AppMain extends Activity {
private Button button;
//JSON對象數組
private String jsonDate = "[{\"name\":\"liuliu\",\"age\":30},{\"name\":\"huohuo\",\"age\":20}]";
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
button = (Button)findViewById(R.id.button);
button.setOnClickListener(new ButtonListener());
}
class ButtonListener implements OnClickListener{
public void onClick(View v) {
Log.d("test", "TEST");
JsonUtils jsonUtils = new JsonUtils();
jsonUtils.parseJson(jsonDate);
}
}
}
========================== <一> END：========================================
==================== <二> 解析一個JSON對象到普通對象：===========================
JsonUtiles.java
view plain
package lxy.litsoft;
import android.util.Log;
import com.google.gson.Gson;
public class JsonUtils {
public void parseUserFromJSON(String jsonDate){
Gson gson = new Gson();
//把JSON對象轉換成類的對象
User user = gson.fromJson(jsonDate, User.class);
Log.d("test", "Name ----> "+user.getName());
Log.d("test", "Age ----> "+user.getAge());
}
}
User.java
view plain
package lxy.litsoft;
public class User {
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;
}
private String name;
private int age;
}
AppMain.java
view plain
package lxy.litsoft;
import android.app.Activity;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
public class AppMain extends Activity {
private Button button;
private String jsonDate = "{\"name\":\"liuliu\",\"age\":30}";
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
button = (Button)findViewById(R.id.button);
button.setOnClickListener(new ButtonListener());
}
class ButtonListener implements OnClickListener{
public void onClick(View v) {
Log.d("test", "TEST");
JsonUtils jsonUtils = new JsonUtils();
jsonUtils.parseUserFromJSON(jsonDate);
}
}
}
接上頁
========================== <二> END：========================================
==================== <三> 解析一個JSON對象數組到普通對象：=======================
JsonUtils.java
view plain
package lxy.litsoft;
import java.lang.reflect.Type;
import java.util.Iterator;
import java.util.LinkedList;
import android.util.Log;
import com.google.gson.Gson;
import com.google.gson.reflect.TypeToken;
public class JsonUtils {
public void parseUserFromJSON(String jsonDate){
Type listType = new TypeToken<LinkedList<User>>(){}.getType();
Gson gson = new Gson();
//把JSON對象轉換成類的對象
LinkedList<User> users = gson.fromJson(jsonDate, listType);
for(Iterator iterator = users.iterator(); iterator.hasNext();){
User user = (User)iterator.next();
Log.d("test", "Name ----> "+user.getName());
Log.d("test", "Age ----> "+user.getAge());
}
}
}
User.java
view plain
package lxy.litsoft;
public class User {
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;
}
private String name;
private int age;
}
AppMain.java
view plain
package lxy.litsoft;
import android.app.Activity;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
public class AppMain extends Activity {
private Button button;
private String jsonDate = "[{\"name\":\"liuliu\",\"age\":30},{\"name\":\"huohuo\",\"age\":20}]";
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
button = (Button)findViewById(R.id.button);
button.setOnClickListener(new ButtonListener());
}
class ButtonListener implements OnClickListener{
public void onClick(View v) {
Log.d("test", "TEST");
JsonUtils jsonUtils = new JsonUtils();
jsonUtils.parseUserFromJSON(jsonDate);
}
}
}
========================== <三> END：========================================