How to parse an XML file in J2ME with kXML

Source code: XmlNode class

First, we'll define an XmlNode class to represent a generic XmlNode. We'll define 2 node types:

• Text nodes: nodes without a name, containing only a textual value
• Element nodes: nodes with a tag name, containing children nodes

Each node will have also a list of attributes.

public class XmlNode
{
public static final int TEXT_NODE = 0;
public static final int ELEMENT_NODE = 1;

public int nodeType = 0;
public String nodeName = null;
public String nodeValue = null;
public Vector children = null;
public Hashtable attributes = null;

public XmlNode(int nodeType)
{
 this.nodeType = nodeType;
 this.children = new Vector();
 this.attributes = new Hashtable();
}
public String[] getAttributeNames()
{
 String[] names = new String[attributes.size()];

 Enumeration e = attributes.keys();

 int i = 0;

 while(e.hasMoreElements())
 {
  names[i] = (String)e.nextElement();
 
  i++;
 }
 return names;
}
public void setAttribute(String key, String value)
{
 attributes.put(key, value);
}
public String getAttribute(String key)
{
 return (String)attributes.get(key);
}

public void addChild(XmlNode child)
{
 this.children.addElement(child);
}
}

Source code: GenericXmlParser class

GenericXmlParser is the class with which we'll able to parse XML files. It has only one public method, parseXML(), that will accept as arguments:

• a KXmlParser instance to do parsing
• a boolean that defines if whitespaces-only children must be ignored

import org.kxml2.io.KXmlParser;
import org.xmlpull.v1.XmlPullParser;

public class GenericXmlParser
{
public XmlNode parseXML(KXmlParser parser,
          boolean ignoreWhitespaces) throws Exception
{
 parser.next();

 return _parse(parser, ignoreWhitespaces);
}
XmlNode _parse(KXmlParser parser,
                boolean ignoreWhitespaces) throws Exception
{
 XmlNode node = new XmlNode(XmlNode.ELEMENT_NODE);

 if(parser.getEventType() != XmlPullParser.START_TAG)
 {
  throw new Exception("Illegal XML state: " +
                                   parser.getName() + ", " + parser.getEventType());
 }
 else
 {
  node.nodeName = parser.getName();
 
  for(int i = 0; i < style="color: rgb(0, 102, 0);">getAttributeCount(); i++)
  {
   node.setAttribute(parser.getAttributeName(i),     parser.getAttributeValue(i));
  }
 
  parser.next();
 
  while(parser.getEventType() != XmlPullParser.END_TAG)
  {
   if(parser.getEventType() == XmlPullParser.START_TAG)
   {
    node.addChild(_parse(parser, ignoreWhitespaces));
   }
   else if(parser.getEventType() == XmlPullParser.TEXT)
   {
    if(!ignoreWhitespaces || !parser.isWhitespace())
    {
     XmlNode child = new XmlNode(XmlNode.TEXT_NODE);
    
     child.nodeValue = parser.getText();
    
     node.addChild(child);
    }
   }
   parser.next();
  }
 }
 return node;
}
}

Source code: sample usage

To use the classes defined above, you can simply do as follows:

InputStreamReader reader = new InputStreamReader(getClass().getResourceAsStream("/test3.xml"));
 
KXmlParser parser = new KXmlParser();
 
parser.setInput(reader);

GenericXmlParser gParser = new GenericXmlParser();
 
XmlNode xml = gParser.parseXML(parser, true);

And, if you want to dump out the parsed XML data, you can use the following method:

void dumpXML(XmlNode node, int deep)
{
for(int i = 0; i < style="color: rgb(102, 204, 102);">)
{
 System.out.print(" ");
}
System.out.print(node.nodeName + " - ");

if(node.nodeValue != null)
{
 System.out.print("(" + node.nodeValue + ") - ");
}
String[] attributes = node.getAttributeNames();

for(int i = 0; i < style="color: rgb(0, 102, 0);">length; i++)
{
 System.out.print(attributes[i] + ": " + node.getAttribute(attributes[i]) + ", ");
}

System.out.println();

for(int i = 0; i < style="color: rgb(0, 102, 0);">children.size(); i++)
{
 dumpXML((XmlNode)node.children.elementAt(i), deep + 1);
}
}

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