在Android应用中使用Pull解析XML文件（传智播客视频笔记）

package com.sinaapp.ssun.service;

import java.io.InputStream;
import java.io.OutputStream;
import java.util.*;

import org.xmlpull.v1.XmlPullParser;
import org.xmlpull.v1.XmlPullParserFactory;
import org.xmlpull.v1.XmlSerializer;

import android.util.Xml;

import com.sinaapp.ssun.domain.Person;

public class Service {
/**
* 获取XML文件中的数据
* @param xml
* @return
* @throws Exception
*/
public static List<Person> getPersons(InputStream xml) throws Exception {
List<Person> persons = null;
XmlPullParser parser = XmlPullParserFactory.newInstance()
.newPullParser();
// parser = Xml.newPullParser();
parser.setInput(xml, "UTF-8");
int event = parser.getEventType();
Person p = null;
while (event != XmlPullParser.END_DOCUMENT) {
switch (event) {
case XmlPullParser.START_DOCUMENT:
persons = new ArrayList<Person>();
break;
case XmlPullParser.START_TAG:
if("person".equals(parser.getName())){
p = new Person();
int id = Integer.parseInt(parser.getAttributeValue(0));
p.setId(id);
}
if("name".equals(parser.getName())){
String name = parser.nextText();
p.setName(name);
}
if("age".equals(parser.getName())){
int age = Integer.parseInt(parser.nextText());
p.setAge(age);
}
break;
case XmlPullParser.END_TAG:
if("person".equals(parser.getName())){
persons.add(p);
p = null;
}
break;
}
event = parser.next();
}
return persons;
}

/**
* 保存数据到XML文件中
* @param persons
* @param out
* @throws Exception
*/
public static void save(List<Person> persons , OutputStream out) throws Exception{
XmlSerializer serializer  =  Xml.newSerializer();
serializer.setOutput(out, "UTF-8");
serializer.startDocument("UTF-8", true);
serializer.startTag(null, "persons");
for(Person p: persons){
serializer.startTag(null, "person");
serializer.attribute(null, "person", p.getId()+"");

serializer.startTag(null, "name");
serializer.text(p.getName());
serializer.endTag(null, "name");

serializer.startTag(null, "age");
serializer.text(p.getAge()+"");
serializer.endTag(null, "age");

serializer.endTag(null, "person");
}
serializer.endTag(null, "persons");
serializer.endDocument();
out.flush();
out.close();
}
}

package com.sinaapp.ssun.domain;

public class Person {
private String name;
private int age;
private int id;

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 int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}

public Person(String name, int age, int id) {
this.name = name;
this.age = age;
this.id = id;
}
public Person() {
super();
}
@Override
public String toString() {
return "Person [name=" + name + ", age=" + age + ", id=" + id + "]";
}
}

<!--test.xml-->
<?xml version="1.0" encoding="UTF-8"?><!-- 开始文档语法 -->
<persons>
<person  id="1">
<name>ssun</name>
<age>19</age>
</person>
<person  id="2">
<name>cobe</name>
<age>24</age>
</person>
</persons>

package com.sinaapp.ssun.test;

import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.util.ArrayList;
import java.util.List;

import android.test.AndroidTestCase;
import android.util.Log;

import com.sinaapp.ssun.domain.Person;
import com.sinaapp.ssun.service.Service;

public class TestService extends AndroidTestCase {
private final String Tag = "Test";

public void testPersons() throws Exception{
List<Person> persons = Service.getPersons(this.getClass().getClassLoader().getResourceAsStream("test.xml"));
for(Person p : persons){
Log.i(Tag, p.toString());
}
}

public void testSave() throws Exception{
List<Person> persons = new ArrayList<Person>();
persons.add(new Person("www",19,23));
persons.add(new Person("hhh",19,3));
persons.add(new Person("qqq",19,24));
persons.add(new Person("ooo",19,25));
File file = new File(this.getContext().getFilesDir(),"test2.xml");
FileOutputStream out = new FileOutputStream(file);
Service.save(persons, out);
}

}