XML Pull Parser

As I told in my previous post The Java programming language provides several standard libraries for processing XML files. The SAX and the DOM XML parsers are also available on Android.

The Java standard provides also the Stax parser. This parser is not part of the Android platform.

On Android it is recommended to use the XmlPullParser. It has a relatively simple API compared to SAX and DOM and is fast and requires less memory then the DOM API.

• There are two key methods: next() and nextToken(). While next() provides access to high level parsing events, nextToken() allows access to lower level tokens.
• The current event state of the parser can be determined by calling the  getEventType() method. Initially, the parser is in the START_DOCUMENT state.
• The method next() advances the parser to the next event.
   The int value returned from next determines the current parser state and is identical
  to the value returned from following calls to getEventType ().

Th following event types are seen by next()

START_TAG

An XML start tag was read.

TEXT

Text content was read; the text content can be retrieved using the getText() method. (when in validating mode next() will not report ignorable whitespace, use nextToken() instead)

END_TAG

An end tag was read

END_DOCUMENT

No more events are available

Exmple:-

 import java.io.IOException;  
  import java.io.StringReader;  
  import org.xmlpull.v1.XmlPullParser;  
  import org.xmlpull.v1.XmlPullParserException.html;  
  import org.xmlpull.v1.XmlPullParserFactory;  
  public class SimpleXmlPullApp  
  {  
    public static void main (String args[])  
      throws XmlPullParserException, IOException  
    {  
      XmlPullParserFactory factory = XmlPullParserFactory.newInstance();  
      factory.setNamespaceAware(true);  
      XmlPullParser xpp = factory.newPullParser();  
      xpp.setInput(new StringReader ("<foo>Hello World!</foo>"));  
      int eventType = xpp.getEventType();  
      while (eventType != XmlPullParser.END_DOCUMENT) {  
      if(eventType == XmlPullParser.START_DOCUMENT) {  
        System.out.println("Start document");  
      } else if(eventType == XmlPullParser.END_DOCUMENT) {  
        System.out.println("End document");  
      } else if(eventType == XmlPullParser.START_TAG) {  
        System.out.println("Start tag "+xpp.getName());  
      } else if(eventType == XmlPullParser.END_TAG) {  
        System.out.println("End tag "+xpp.getName());  
      } else if(eventType == XmlPullParser.TEXT) {  
        System.out.println("Text "+xpp.getText());  
      }  
      eventType = xpp.next();  
      }  
    }  
  }   

Happy Coding....