Hello Android - PULL方式解析XML

Android中解析XML的方式有三种,DOM方式是将全部文件解析到内存中,再进行操作,对于手机来说太耗内存了;SAX和PULL都采用事件驱动的方式,边读边解析。在看过几种之后觉得PULL比较好记。以下是摘录的代码:

import java.io.InputStream;
import java.io.OutputStream;
import java.io.Writer;
import java.util.ArrayList;
import java.util.List;

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

import android.util.Xml;

import cn.itcast.domain.Person;
/**
 * 采用Pull解析XML内容
 */
public class PULLPersonService {

public static void save(List<Person> persons, Writer writer) throws Throwable{
XmlSerializer serializer = Xml.newSerializer();
serializer.setOutput(writer);
serializer.startDocument("UTF-8", true);

serializer.startTag(null, "persons");
for(Person person : persons){
serializer.startTag(null, "person");
serializer.attribute(null, "id", person.getId().toString());

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

serializer.startTag(null, "age");
serializer.text(person.getAge().toString());
serializer.endTag(null, "age");

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

public static List<Person> getPersons(InputStream inStream) throws Throwable{
List<Person> persons = null;
Person person = null;
XmlPullParser parser = Xml.newPullParser();
parser.setInput(inStream, "UTF-8");
int eventType = parser.getEventType();//产生第一个事件
while(eventType!=XmlPullParser.END_DOCUMENT){//只要不是文档结束事件
switch (eventType) {
case XmlPullParser.START_DOCUMENT://如果是
persons = new ArrayList<Person>();
break;

case XmlPullParser.START_TAG:
String name = parser.getName();//获取解析器当前指向的元素的名称
if("person".equals(name)){
person = new Person();
person.setId(new Integer(parser.getAttributeValue(0)));
}
if(person!=null){
if("name".equals(name)){
person.setName(parser.nextText());//获取解析器当前指向元素的下一个文本节点的值
}
if("age".equals(name)){
person.setAge(new Short(parser.nextText()));
}
}
break;

case XmlPullParser.END_TAG:
if("person".equals(parser.getName())){
persons.add(person);
person = null;
}
break;
}
eventType = parser.next();
}
return persons;
}
}