Zusammenfassung der drei Methoden zum Betrieb von XML in Android

package cn.itcast.service;
import java.io.InputStream;import java.util.ArrayList;import java.util.List;
import javax.xml.parsers.DocumentBuilder;import javax.xml.parsers.DocumentBuilderFactory;
import org.w3c.dom.Document;import org.w3c.dom.Element;import org.w3c.dom.Node;import org.w3c.dom.NodeList;
import cn.itcast.model.Person;
public class DomPersonService {
  public List<Person> getPersons(InputStream stream) throws Throwable
  {
   List<Person> list =new ArrayList<Person>();
   DocumentBuilderFactory factory =DocumentBuilderFactory.newInstance();
   DocumentBuilder builder =factory.newDocumentBuilder();
   Document dom = builder.parse(stream);//解析完成，并以dom树的方式存放在内存中。比较消耗性能
   //开始使用dom的api去解析
   Element root = dom.getDocumentElement();//根元素
    NodeList personNodes = root.getElementsByTagName("person");//返回所有的person元素节点
  //开始遍历啦
  for(int i=0;i<personNodes.getLength();i++)
  {
   Person person =new Person();
  Element personElement =(Element)personNodes.item(i);
    person.setId(new Integer( personElement.getAttribute("id")));//将person元素节点的属性节点id的值，赋给person对象
    NodeList personChildrenNodes =personElement.getChildNodes();//获取person节点的所有子节点
    //遍历所有子节点
    for(int j=0;j<personChildrenNodes.getLength();j++)
    {
     //判断子节点是否是元素节点（如果是文本节点，可能是空白文本，不处理）
     if(personChildrenNodes.item(j).getNodeType()==Node.ELEMENT_NODE)
     { 
      //子节点--元素节点
      Element childNode =(Element)personChildrenNodes.item(j);
           if("name".equals(childNode.getNodeName()))
         {
          //如果子节点的名称是“name”.将子元素节点的第一个子节点的值赋给person对象
           person.setName(childNode.getFirstChild().getNodeValue());
          }else if("age".equals(childNode.getNodeValue()))
         {
           person.setAge(new Integer(childNode.getFirstChild().getNodeValue()));
         }
     }
    }
    list.add(person);
  }
  return list;
  }}

package cn.itcast.service;
import java.io.InputStream;import java.util.ArrayList;import java.util.List;
import javax.xml.parsers.SAXParser;import javax.xml.parsers.SAXParserFactory;
import org.xml.sax.Attributes;import org.xml.sax.SAXException;import org.xml.sax.helpers.DefaultHandler;
import cn.itcast.model.Person;
public class SAXPersonService {   public List<Person> getPersons(InputStream inStream) throws Throwable
   {
    SAXParserFactory factory = SAXParserFactory.newInstance();//工厂模式还是单例模式？
    SAXParser parser =factory.newSAXParser();
    PersonParse personParser =new PersonParse();
    parser.parse(inStream, personParser);
    inStream.close();
    return personParser.getPerson();
   }
   private final class PersonParse extends DefaultHandler
   {  private List<Person> list = null;
    Person person =null;
    private String tag=null;
    public List<Person> getPerson()
     {
       return list;
        }
    @Override public void startDocument() throws SAXException
     {
      list =new ArrayList<Person>();
      }
 @Override public void startElement(String uri, String localName, String qName,
   Attributes attributes) throws SAXException {
  if("person".equals(localName))
  {
   //xml元素节点开始时触发，是“person”
   person = new Person();
   person.setId(new Integer(attributes.getValue(0)));
  }
  tag =localName;//保存元素节点名称 } @Override public void endElement(String uri, String localName, String qName)
   throws SAXException {
  //元素节点结束时触发，是“person”
  if("person".equals(localName))
  {
   list.add(person);
   person=null;
  }
  tag =null;//结束时，需要清空tag
  } @Override public void characters(char[] ch, int start, int length)
   throws SAXException {  if(tag!=null)
  {
   String data = new String(ch,start,length);
     if("name".equals(tag))
     {
     person.setName(data);
     }else if("age".equals(tag))
     {
       person.setAge(new Integer(data));
       }
     }
    }
  }
}

package cn.itcast.service;
import java.io.InputStream;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.model.Person;
public class PullPersonService { //保存xml文件 public static void saveXML(List<Person> list,Writer write)throws Throwable
 {  XmlSerializer serializer =Xml.newSerializer();//序列化
 serializer.setOutput(write);//输出流
 serializer.startDocument("UTF-8", true);//开始文档
 serializer.startTag(null, "persons");
   //循环去添加person
  for (Person person : list) {
   serializer.startTag(null, "person");
   serializer.attribute(null, "id", person.getId().toString());//设置id属性及属性值
   serializer.startTag(null, "name");
   serializer.text(person.getName());//文本节点的文本值--name
   serializer.endTag(null, "name");   serializer.startTag(null, "age");
   serializer.text(person.getAge().toString());//文本节点的文本值--age
   serializer.endTag(null, "age");   serializer.endTag(null, "person");
       }
    serializer.endTag(null, "persons");
    serializer.endDocument();
    write.flush();
    write.close(); }
    public List<Person> getPersons(InputStream stream) throws Throwable
      {
       List<Person> list =null;
       Person person =null;
       XmlPullParser parser =Xml.newPullParser();
       parser.setInput(stream,"UTF-8");
     int type =parser.getEventType();//产生第一个事件
       //只要当前事件类型不是”结束文档“，就去循环
       while(type!=XmlPullParser.END_DOCUMENT)
      {
    switch (type) {
    case XmlPullParser.START_DOCUMENT:
    list = new ArrayList<Person>();
    break;
      case XmlPullParser.START_TAG:
    String name=parser.getName();//获取解析器当前指向的元素名称
    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的元素的下一个文本节点的文本值
    }
    if("age".equals(name))
    {
     person.setAge(new Integer(parser.nextText()));
    }
   }
   break;
  case XmlPullParser.END_TAG:
   if("person".equals(parser.getName()))
   {
    list.add(person);
    person=null;
   }
     break;
    }
     type=parser.next();//这句千万别忘了哦
     }
   return list;
  }
}

package cn.itcast.model;
public class Person {private Integer id;public Integer getId() { return id;}public void setId(Integer id) { this.id = id;}
private String name;public String getName() { return name;}
public void setName(String name) { this.name = name;}
private Integer age;public Integer getAge() { return age;}
public void setAge(Integer age) { this.age = age;}
public Person(){}public Person(Integer id, String name, Integer age) { this.id = id; this.name = name; this.age = age;}
@Overridepublic String toString() { return "Person [id=" + id + ", name=" + name + ", age=" + age + "]";}
}