This is the main file for Kik

Kik.java

package com.arthurnn;

import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
import java.util.HashMap;
import java.util.List;
import java.util.Map.Entry;

import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.xpath.XPath;
import javax.xml.xpath.XPathConstants;
import javax.xml.xpath.XPathExpression;
import javax.xml.xpath.XPathFactory;

import org.w3c.dom.Document;
import org.w3c.dom.NodeList;

public class Kik {

	/**
	 * @param args
	 * @throws Exception
	 */
	public static void main(String[] args) throws Exception {
		final HashMap<String, Integer> _words_count = new HashMap<String, Integer>();

		String URL = "http://rss.cbc.ca/lineup/topstories.xml";

		DocumentBuilderFactory domFactory = DocumentBuilderFactory
				.newInstance();

		DocumentBuilder builder = domFactory.newDocumentBuilder();
		Document doc = builder.parse(URL);

		XPath xpath = XPathFactory.newInstance().newXPath();
		// XPath Query for showing all nodes value
		XPathExpression expr = xpath.compile("/rss/channel/item/link/text()");

		Object result = expr.evaluate(doc, XPathConstants.NODESET);
		NodeList nodes = (NodeList) result;

		List<Thread> threads = new ArrayList<Thread>();
		for (int i = 0; i < nodes.getLength(); i++) {
			String link = nodes.item(i).getNodeValue();
			MapReduceThread thread = new MapReduceThread(link, _words_count);

			thread.start();
			//thread.join();
			
			threads.add(thread);
		}

		for (Thread thread : threads) {
			thread.join();
		}

		Comparator<Entry<String,Integer>> comparator = new Comparator<Entry<String,Integer>>()  
		{  
			@Override
			public int compare(Entry<String, Integer> arg0,
					Entry<String, Integer> arg1) {
				return arg1.getValue().compareTo(arg0.getValue());
			}  
		};  
		
		List<Entry<String,Integer>> entries = new ArrayList<Entry<String,Integer>>();
		entries.addAll(_words_count.entrySet()); 
		Collections.sort(entries, comparator);
		
//		System.out.println(entries.size());
		int c = 0;
		for (Entry<String,Integer> e : entries) {
			if (c >= 50) break;
			System.out.println(++c + " " + e.getValue() + " " + e.getKey());
		}

	}

}

MapReduceThread.java

package com.arthurnn;

import java.util.HashMap;
import java.util.Map.Entry;

import org.htmlcleaner.CleanerProperties;
import org.htmlcleaner.HtmlCleaner;
import org.htmlcleaner.TagNode;

public class MapReduceThread extends Thread {
	private String link = null;

	private HashMap<String, Integer> _words_count;

	public MapReduceThread(String link, HashMap<String, Integer> _words_count) {
		this.link = link;
		this._words_count = _words_count;
	}

	@Override
	public void run() {
		final HashMap<String, Integer> words_count = new HashMap<String, Integer>();

		try {
			CleanerProperties props = new CleanerProperties();
			final HtmlCleaner htmlCleaner = new HtmlCleaner(props);
			TagNode tagNode = htmlCleaner.clean(new java.net.URL(link));
			Object[] myNodes = tagNode
					.evaluateXPath("//div[@id='storybody']/p/text()");
			
			for (int i = 0; i < myNodes.length; i++) {
				String doc = String.valueOf(myNodes[i]);

				String arr[] = doc.split("\\s+");
				for (String key : arr) {
					key = key.replace("'","").replace("\"", "");
					
					Integer c = words_count.get(key);
					if (null == c) {
						words_count.put(key, 1);
					} else {
						words_count.put(key, c + 1);
					}
				}

			}
			
			synchronized (_words_count) {
				for (Entry<String, Integer> e : words_count.entrySet()) {
					String key = e.getKey();
					Integer n = _words_count.get(key);
					if (null == n) {
						n = 0;
					}
					_words_count.put(key, n + e.getValue());
				}
			}
		} catch (Exception e) {
			throw new RuntimeException(e);
		}

	}
}