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The Jadex nuggets is a fast Java bean to XML and back converter.
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/*
 * JavaXMLWriter.java
 * Copyright (c) 2005 by University of Hamburg. All Rights Reserved.
 * Departament of Informatics. 
 * Distributed Systems and Information Systems.
 *
 * Created by walczak on Jan 11, 2006.  
 * Last revision $Revision: 6926 $ by:
 * $Author: braubach $ on $Date: 2008-09-28 22:16:58 +0200 (So, 28 Sep 2008) $.
 */
package nuggets;

import java.io.IOException;
import java.io.Reader;

import nuggets.util.Base64;
import nuggets.util.CharStream;

import org.xmlpull.v1.XmlPullParser;
import org.xmlpull.v1.XmlPullParserException;
import org.xmlpull.v1.XmlPullParserFactory;


/**
 * JavaXMLWriter - writes a raw XML with java packages for ontology purpose.
 * This can be used only with java.
 * 
 * @author walczak
 * @since Jan 11, 2006
 */
public class JavaXMLReader implements IReader
{
	private XmlPullParser	xpp;
	
	private final CharStream cs = new CharStream();

	/** Initializes the Reader
	 * Constructor for JavaXMLReader.
	 */
	public JavaXMLReader()  {
		try
		{
			XmlPullParserFactory factory = XmlPullParserFactory.newInstance();
			xpp = factory.newPullParser();
		}
		catch(XmlPullParserException e)
		{
			throw new PersistenceException(e);
		}
	}
	
	/**
	 * @param rdr
	 * @see nuggets.IReader#start(java.io.Reader)
	 */
	public void start(Reader rdr)
	{
		try
		{
			xpp.setInput(rdr);
			int i;
			while((i = xpp.next())!=XmlPullParser.START_TAG) {
				if (i==XmlPullParser.END_DOCUMENT) throw new PersistenceException("Input ended befor the first element");
			}
			String name;
			if (!"n:root".equals(name = xpp.getName())) {
				throw new PersistenceException("Encountered wrong element: "+name);
			}
			attributes=readAttributes();
		}
		catch(XmlPullParserException e)
		{
			throw new PersistenceException(e);
		}
		catch(IOException e)
		{
			throw new PersistenceException(e);
		}
	}
	
	final Buffer buffer = new Buffer();
	
	final int[]	oAndL = new int[2];

	private String[]	attributes;

	/**
	 * @return a 
	 * @see nuggets.IReader#getText()
	 */
	public Buffer getText()
	{
		int i;
		try
		{
			while((i = xpp.next())!=XmlPullParser.TEXT) {
				if (i==XmlPullParser.END_DOCUMENT || i==XmlPullParser.END_TAG) {
					buffer.set(null, 0, 0);
					return buffer;
				}
			}
			buffer.set(xpp.getTextCharacters(oAndL), oAndL[0], oAndL[1]);
			return buffer;
		}
		catch(XmlPullParserException e)
		{
			throw new PersistenceException(e);
		}
		catch(IOException e)
		{
			throw new PersistenceException(e);
		}
	}
	
	/** 
	 * @return byte array from the text element encoded in Base64
	 * @see nuggets.IReader#getData()
	 */
	public byte[] getData()
	{
		int i;
		try
		{
			while((i = xpp.next())!=XmlPullParser.TEXT) {
				if (i==XmlPullParser.END_DOCUMENT) {
					return null;
				}
			}
			buffer.set(xpp.getTextCharacters(oAndL), oAndL[0], oAndL[1]);
			return Base64.decode(buffer.chars, buffer.start, buffer.len);
		}
		catch(XmlPullParserException e)
		{
			throw new PersistenceException(e);
		}
		catch(IOException e)
		{
			throw new PersistenceException(e);
		}
	}

	/**
	 * @return the name of the next element or null
	 * @see nuggets.IReader#nextElement()
	 */
	public String nextElement()
	{
		int i;
		try
		{
			while((i = xpp.next())!=XmlPullParser.START_TAG) {
				if (i==XmlPullParser.END_DOCUMENT) return null;
			}
			attributes=readAttributes();
			return decodeTag(xpp.getName());
		}
		catch(XmlPullParserException e)
		{
			throw new PersistenceException(e);
		}
		catch(IOException e)
		{
			throw new PersistenceException(e);
		}
	}

	

	/** 
	 * @return the attributes decoded
	 */
	private String[] readAttributes()
	{
		int count=xpp.getAttributeCount();
		String[] attr=new String[count];
		for(int i=0; i