Android developed DOM method for parsing xml files

This article gives an example of how DOM parses xml files in Android. To share for your reference, the details are as follows:

1. Write xml files in assets files

<?xml version="1.0" encoding="UTF-8"?> 
<persons> 
 <person id="23"> 
  <name> Li Ming </name> 
  <age>30</age> 
 </person> 
 <person id="20"> 
  <name> Li Xiangmei </name> 
  <age>25</age> 
 </person> 
</persons>

2. Write an DOM parse operation in service

package com.example.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 com.example.domain.Person; 
public class XMLDomService { 
 public List<Person> parseXML(InputStream is) { 
  List<Person> list = new ArrayList<Person>(); 
  //  create DOM A factory object  
  DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
  try { 
   // DocumentBuilder object  
   DocumentBuilder builder = factory.newDocumentBuilder(); 
   //  Get the document object  
   Document document = builder.parse(is); 
   //  Gets the document object root 
   Element root = document.getDocumentElement(); 
   //  To obtain persons All of the root nodes person The node object  
   NodeList personNodes = root.getElementsByTagName("person"); 
   //  I'm going through all of them person node  
   for (int i = 0; i < personNodes.getLength(); i++) { 
    Person person = new Person(); 
    //  According to the item(index) Gets the node object corresponding to the index  
    Element personNode = (Element) personNodes.item(i); //  specific person node  
    //  Set up the id Attribute values  
    person.setId(Integer.parseInt(personNode.getAttribute("id")));
    //  Gets all the byte points below the node  
    NodeList personChildNodes = personNode.getChildNodes(); 
    //  traverse person The byte points  
    for (int index = 0; index < personChildNodes.getLength(); index++) { 
     //  Get child nodes  
     Node node = personChildNodes.item(index); 
     //  judge node Whether the node is an element node  
     if (node.getNodeType() == Node.ELEMENT_NODE) { 
      // Converts nodes into element nodes  
      Element element = (Element) node; 
      // Determine if the element node is name Element nodes  
      if ("name".equals(element.getNodeName())) { 
       person.setName(element.getFirstChild() 
         .getNodeValue()); 
      } else if ("age".equals(element.getNodeName())) { // Judge whether or not age node  
       person.setAge(new Short(element.getFirstChild().getNodeValue()));
      } 
     } 
    } 
    //  the person Object is added to the collection  
    list.add(person); 
   } 
   // Close the input stream  
   is.close(); 
  } catch (Exception e) { 
   // TODO Auto-generated catch block 
   e.printStackTrace(); 
  } 
  return list; 
 } 
}

3. Display operations in Activity

package com.example.lession03_xml;
import java.io.InputStream;
import java.util.List;
import javax.xml.parsers.SAXParser;
import javax.xml.parsers.SAXParserFactory;
import com.example.domain.Person;
import com.example.service.XMLContentHandler;
import com.example.service.XMLDomService;
import android.os.Bundle;
import android.app.Activity;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.inputmethod.InputBinding;
import android.widget.Button;
import android.widget.Toast;
public class XmlActivityextends Activity {
// Announcement component 
public Button btn_sax,btn_dom,btn_pull;
public XMLDomService xmlDomService;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// Set the view to display 
setContentView(R.layout.activity_xml);
xmlDomService=new XMLDomService();
// According to the id Access to the component 
btn_sax=(Button) findViewById(R.id.btn_sax);
btn_dom=(Button) findViewById(R.id.btn_dom);
btn_pull=(Button) findViewById(R.id.btn_pull);
// Register the event for the button 
btn_sax.setOnClickListener(new MyOnclickListener());
btn_dom.setOnClickListener(new MyOnclickListener());
btn_pull.setOnClickListener(new MyOnclickListener());
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.xml, menu);
return true;
}
// An anonymous class 
class MyOnclickListener implements OnClickListener{
@Override
public void onClick(View v) {
int id=v.getId();
switch (id) {
case R.id.btn_sax:
Toast.makeText(XmlActivity.this," using SAX parsing ", Toast.LENGTH_LONG).show();
try{
//SAX Resolved factory object 
SAXParserFactory factory=SAXParserFactory.newInstance();
// get sax The parser 
SAXParser saxParser=factory.newSAXParser();
// create handler object 
XMLContentHandler handlerService=new XMLContentHandler();
InputStream is=getAssets().open("csdn.xml");
// Direct analytical 
saxParser.parse(is, handlerService);
// through handlerService Object to obtain 
Toast.makeText(XmlActivity.this,"----"+handlerService, Toast.LENGTH_LONG).show();
}catch(Exception e){
e.printStackTrace();
}
break;
case R.id.btn_dom:
InputStream is=null;
try{
// Gets the input stream object that reads the file 
is=getAssets().open("csdn.xml");
// using dom parsing 
List<Person> persons=xmlDomService.parseXML(is);
// A simple test 
//Toast.makeText(XmlActivity.this, ""+persons.get(0).getName(), Toast.LENGTH_LONG).show();
Toast.makeText(XmlActivity.this," using DOM parsing "+persons.get(0).getName(), Toast.LENGTH_LONG).show();
}catch(Exception e){
e.printStackTrace();
}
break;
case R.id.btn_pull:
Toast.makeText(XmlActivity.this," using PULL parsing ", Toast.LENGTH_LONG).show();
break;
default:
break;
}
}
}
}

I hope this article has been helpful in Android programming.