import java.io.IOException;


import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;

import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.NamedNodeMap;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
import org.w3c.dom.Text;
import org.xml.sax.SAXException;

public class DomParser
{
	public void createNode(Document doc)throws IOException
	{
		Node rootNode = doc.getDocumentElement();
		Element element = doc.createElement("book");		
		element.setAttribute("category","Java");
		
		Node nodeTitle = doc.createElement("title");
		Text textTitle = doc.createTextNode("Java world");
		nodeTitle.appendChild(textTitle);
		
		Node nodeAuthor = doc.createElement("author");
		Text textAuthor = doc.createTextNode("Ahmed Hashim");
		nodeAuthor.appendChild(textAuthor);
		
		element.appendChild(nodeTitle);
		element.appendChild(nodeAuthor);
		
		rootNode.appendChild(element);
		
	}
	
	public void parseNode(Node node)throws IOException
	{
		NodeList nodes = null;
		if(node.getNodeType() == Node.DOCUMENT_NODE)
		{
			System.out.println("/* Catalog contain books*/");
		
		nodes = node.getChildNodes();
		if(nodes != null)
		{
			for (int i = 0; i < nodes.getLength(); i++)
			{
				parseNode(nodes.item(i));
			}
		}
		}
		else if(node.getNodeType() == Node.ELEMENT_NODE)
		{
			NamedNodeMap attrs = node.getAttributes();
			for (int i = 0; i < attrs.getLength(); i++)
			{
				System.out.println("Category: "+attrs.item(i).getNodeValue());
			}
			if(node.getNodeName().equals("title"))
			{
				System.out.print("Title:");
			}
			else if(node.getNodeName().equals("author"))
			{
				System.out.print("Author:");
			}
			nodes = node.getChildNodes();
			if(nodes != null)
			{
				for (int i = 0; i < nodes.getLength(); i++)
				{
					parseNode(nodes.item(i));
				}
			}
		}
		else if(node.getNodeType() == Node.TEXT_NODE)
		{
			if(node.getNodeValue().length()>3)
			{
				System.out.println(node.getNodeValue());
			}
		}
		
	}
	public static void main(String[] args)
	{
		try
		{
			DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
			DocumentBuilder builder = factory.newDocumentBuilder();
			Document doc = builder.parse("books.xml");
			DomParser dom = new DomParser();
			dom.createNode(doc);
			dom.parseNode(doc);
		}
		catch (ParserConfigurationException e)
		{
			e.printStackTrace();
		}
		catch (SAXException e)
		{
			e.printStackTrace();
		}
		catch (IOException e)
		{
			e.printStackTrace();
		}
		
	}
}