diff --git a/WikiRating/src/main/java/computations/CreditSystem.java b/WikiRating/src/main/java/computations/CreditSystem.java
new file mode 100644
index 0000000..29242cb
--- /dev/null
+++ b/WikiRating/src/main/java/computations/CreditSystem.java
@@ -0,0 +1,109 @@
+package main.java.computations;
+
+
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.Iterator;
+import java.util.List;
+import java.util.Map;
+
+import javax.ws.rs.GET;
+import javax.ws.rs.Path;
+import javax.ws.rs.Produces;
+import javax.ws.rs.QueryParam;
+
+import org.codehaus.jettison.json.JSONArray;
+import org.codehaus.jettison.json.JSONException;
+import org.json.JSONObject;
+
+import com.tinkerpop.blueprints.Direction;
+import com.tinkerpop.blueprints.Edge;
+import com.tinkerpop.blueprints.Vertex;
+import com.tinkerpop.blueprints.impls.orient.OrientGraph;
+import com.tinkerpop.blueprints.impls.orient.OrientVertex;
+
+import main.java.utilities.Connections;
+
+@Path("credit")
+@Produces("application/json")
+public class CreditSystem {
+	
+	@GET
+	@Path("users")
+	@Produces("application/json")
+	public static String generateCredits(@QueryParam("name") List<String> pageList,@QueryParam("join") boolean join){
+		OrientGraph graph = Connections.getInstance().getDbGraph();
+		
+		if(join){
+			Vertex pageNode=null;
+			for(int i=0;i<pageList.size();i++){
+				pageNode=graph.getVertices("title",pageList.get(i)).iterator().next();
+				HashMap<Integer,Integer> userContributions=new HashMap<Integer,Integer>();
+				getUserContributions(graph,userContributions,pageNode);
+				
+				
+			}
+			
+			
+			graph.shutdown();
+			return "Success";
+			
+		}
+		
+		
+		else{
+			graph.shutdown();
+			return "Success";
+			
+	}
+
+}
+	
+	/**
+	 * @param graph
+	 * @param userContributions
+	 * @param pageNode
+	 */
+	public static void getUserContributions(OrientGraph graph,HashMap<Integer,Integer> userContributions,Vertex pageNode){
+		Vertex revisionNode=null,userNode=null;
+		revisionNode=pageNode.getEdges(Direction.OUT, "@class", "PreviousVersionOfPage").iterator().next().getVertex(Direction.IN);
+		Edge contribute=null;
+		int contributionSize=0,userid=0;
+		try{
+		while(true){
+			 
+			contribute=revisionNode.getEdges(Direction.IN, "@class", "Contribute").iterator().next();
+			userNode=contribute.getVertex(Direction.OUT);
+			 
+			 //Get the required bytes and the corresponding userid
+			contributionSize=contribute.getProperty("contributionSize");
+			userid=userNode.getProperty("userid"); //Putting the data into the HashMap
+			 
+			 if(userContributions.containsKey(userid)){
+			 
+				 userContributions.put(userid, userContributions.get(userid)+contributionSize);
+			 
+			 }
+			 else{
+			
+				 userContributions.put(userid, contributionSize);
+			 
+			 }
+			 
+			 if((int)revisionNode.getProperty("parentid")!=0)
+				 break;
+			 
+			revisionNode=graph.getVertices("revid", (int)revisionNode.getProperty("parentid")).iterator().next();
+			
+		}
+		}catch(Exception e){
+			e.printStackTrace();
+		}
+		
+		Iterator it = userContributions.entrySet().iterator();
+		while (it.hasNext()) {
+			Map.Entry pair = (Map.Entry) it.next();
+			System.out.println(pair.getKey()+"   "+pair.getValue());
+		}
+	}
+}
diff --git a/WikiRating/src/main/java/controllers/DisplayStatistics.java b/WikiRating/src/main/java/controllers/DisplayStatistics.java
index a50df75..6963c97 100644
--- a/WikiRating/src/main/java/controllers/DisplayStatistics.java
+++ b/WikiRating/src/main/java/controllers/DisplayStatistics.java
@@ -1,48 +1,49 @@
 package main.java.controllers;
 
 import javax.ws.rs.GET;
 import javax.ws.rs.Path;
 import javax.ws.rs.Produces;
 import javax.ws.rs.QueryParam;
 
 import org.glassfish.jersey.server.JSONP;
 
 import com.tinkerpop.blueprints.Vertex;
 import com.tinkerpop.blueprints.impls.orient.OrientGraph;
 
 import main.java.utilities.Connections;
 import main.java.utilities.PropertiesAccess;
 
 @Path("stats")
 
 public class DisplayStatistics {
 
 	@GET
 	@Path("display")
 	@JSONP(queryParam = "callback")
 	@Produces({ "application/x-javascript" })
 	public String getAllStats(@QueryParam("callback") String callback, @QueryParam("pageTitle") String pageTitle) {
 		int nameSpace,badgeNumber;long totalVotes=0;
 		double pageRank,currentPageVote,pageReliability,maxPageReliability,maxPageRank;
 		OrientGraph graph = Connections.getInstance().getDbGraph();
 		Vertex pageNode=graph.getVertices("title",pageTitle).iterator().next();
 		
 		nameSpace=pageNode.getProperty("namespace");
 		badgeNumber=pageNode.getProperty("badgeNumber");
 		pageRank=pageNode.getProperty("Pagerank");
 		totalVotes=pageNode.getProperty("totalVotes");
 		currentPageVote=pageNode.getProperty("currentPageVote");
 		pageReliability=pageNode.getProperty("currentPageReliability");
 		maxPageReliability=PropertiesAccess.getParameter("maxPageReliability");
 		maxPageRank=PropertiesAccess.getParameter("maxPageRank");
 		
 		graph.shutdown();
 		System.out.println(nameSpace+" "+badgeNumber+" "+pageRank+" "+totalVotes+" "+currentPageVote+" "+pageReliability+" "+maxPageReliability+" "+maxPageRank);
 		
-		String sJson="{\"pageTitle\":\"dd\",\"currentPageRating\":2,\"maxPageRating\":55,\"badgeNumber\":4}";
+		//String sJson="{\"pageTitle\":\"dd\",\"currentPageRating\":2,\"maxPageRating\":55,\"badgeNumber\":4}";
 		
+		String sJson="{\"nameSpace\":"+nameSpace+",\"badgeNumber\":"+badgeNumber+",\"pageRank\":"+pageRank+",\"totalVotes\":"+totalVotes+",\"currentPageVote\":"+currentPageVote+",\"pageReliability\":"+pageReliability+",\"maxPageReliability\":"+maxPageReliability+",\"maxPageRank\":"+maxPageRank+"}";
 		String result = callback + "(" + sJson + ");";
 		return result;
 
 	}
 }
diff --git a/WikiRating/src/main/java/controllers/Firstrun.java b/WikiRating/src/main/java/controllers/Firstrun.java
index 7f6980e..c6655e9 100644
--- a/WikiRating/src/main/java/controllers/Firstrun.java
+++ b/WikiRating/src/main/java/controllers/Firstrun.java
@@ -1,90 +1,94 @@
 package main.java.controllers;
 
 import javax.ws.rs.GET;
 import javax.ws.rs.Path;
 import javax.ws.rs.Produces;
 import javax.ws.rs.core.Response;
 
+import com.orientechnologies.orient.core.Orient;
+
 import main.java.computations.BadgeGenerator;
 import main.java.computations.NormalisedVotes;
 import main.java.computations.PageRating;
 import main.java.computations.Pagerank;
 import main.java.computations.RandomVoteGenerator;
 import main.java.computations.Reliability;
 import main.java.computations.UserCredibility;
 import main.java.models.InitialiseDB;
 import main.java.models.LinkPages;
 import main.java.models.LinkUserContributions;
 import main.java.models.Page;
 import main.java.models.Revision;
 import main.java.models.User;
 
 
 /**
  * This class will be used to initialize the engine. 
  * 
  */
 @Path("firstRun")
 public class Firstrun {
 	
 
 	@GET
 	@Produces("application/json")
 	
 	// Warning: If you add revisions before the Users, only those users who have
 	// not contributed to Wiki will be added.
 	// However this behaviour can be inverted too
 	
 	/**
 	 * This method will call different other methods that will initialize the engine
 	 * @return Response object showing time taken to run the computation
 	 */
 	public Response pCompute() {
 		long startTime = System.currentTimeMillis();
 		
 		InitialiseDB.createClass();
 		System.out.println("==================Classes creation over=====================");
 		
 		Page.insertPages();
 		System.out.println("==================Page insertion over=====================");
 		
 		LinkPages.linkAll("@class","Page");
 		System.out.println("==================Page linking over=====================");
 		
-		User.insertAllUsers();
+		Orient.instance().shutdown();
+		
+		/*User.insertAllUsers();
 		System.out.println("==================All Users inserted=====================");
 		
 		Revision.getAllRevisions("@class","Page");
 		System.out.println("==================Page Revisions over=====================");
 		
 		Pagerank.pageRankCompute();
 		System.out.println("==================Page rank over=====================");
 		
 		LinkUserContributions.linkAll();
 		System.out.println("==================All Users Linked=====================");
 		
 		RandomVoteGenerator.generateVotes();
 		System.out.println("==================All Versions voted=====================");
 		
 		NormalisedVotes.calculatePageVotes();
 		System.out.println("==================All Page Votes computed=====================");
 		
 		UserCredibility.getUserCredibility();
 		System.out.println("==================User Credibility computed=====================");
 		
 		Reliability.calculateReliability();
 		System.out.println("==================Vote Reliability computed=====================");
 		
 		PageRating.computePageRatings();
 		System.out.println("==================Page Ratings computed=====================");
 		
 		new BadgeGenerator().generateBadges();
-		System.out.println("==================Badges given=====================");
+		System.out.println("==================Badges given=====================");*/
 		
 		long estimatedTime = System.currentTimeMillis() - startTime;
 		estimatedTime = estimatedTime / 60000;
 
 		return Response.status(200).entity("Successful and took" + estimatedTime + "Minutes").build();
 	}
 
 }
diff --git a/WikiRating/src/main/java/models/InitialiseDB.java b/WikiRating/src/main/java/models/InitialiseDB.java
index 8cf82de..6d809ba 100644
--- a/WikiRating/src/main/java/models/InitialiseDB.java
+++ b/WikiRating/src/main/java/models/InitialiseDB.java
@@ -1,44 +1,47 @@
 package main.java.models;
 
 import com.tinkerpop.blueprints.impls.orient.OrientGraphNoTx;
 import main.java.utilities.Connections;
 
 
 /**
  * This class will be used only for the creation of the classes in the database.
   */
 
 public class InitialiseDB {
 
 
 	/**
 	 * This method will create  various classes in the database 
 	 */
 	public static void createClass() {
+		// No transaction to avoid warnings
 		OrientGraphNoTx graph = Connections.getInstance().getDbGraphNT();
 		graph.createVertexType("Page");
 		System.out.println("====Created Class Page====");
 		
 		graph.createVertexType("User");
 		System.out.println("====Created Class User====");
 		
 		graph.createVertexType("Revision");
 		System.out.println("====Created Class Revision====");
 		
 		graph.createEdgeType("Backlink");
 		System.out.println("====Created Class Backlink====");
 		
 		graph.createEdgeType("PreviousRevision");
 		System.out.println("====Created Class PreviousRevision====");
 		
 		graph.createEdgeType("PreviousVersionOfPage");
 		System.out.println("====Created Class PreviousVersionOfPage====");
 		
 		graph.createEdgeType("Contribute");
 		System.out.println("====Created Class Contribute====");
 		
 		graph.createEdgeType("Review");
 		System.out.println("====Created Class Review====");
+		
+		graph.shutdown();
 	}
 
 }
diff --git a/WikiRating/src/main/java/models/LinkPages.java b/WikiRating/src/main/java/models/LinkPages.java
index 19e8f86..d5e974a 100644
--- a/WikiRating/src/main/java/models/LinkPages.java
+++ b/WikiRating/src/main/java/models/LinkPages.java
@@ -1,107 +1,109 @@
 package main.java.models;
 
 import java.io.InputStream;
 import org.json.JSONArray;
 import org.json.JSONException;
 import org.json.JSONObject;
 import org.wikidata.wdtk.wikibaseapi.ApiConnection;
 import com.tinkerpop.blueprints.Edge;
 import com.tinkerpop.blueprints.Vertex;
 import com.tinkerpop.blueprints.impls.orient.OrientGraph;
 import main.java.controllers.WikiUtil;
 import main.java.utilities.Connections;
 
 
 /**
  * This class will deal with the procedures to links the pages which points to some other pages.
  * So this will interconnect all the Backlinks. 
  */
 
 public class LinkPages {
 	
 	/**
 	 * This method will link all the Pages in the database
 	 * @param key	Name of the key here '@class'
 	 * @param value	Value of the key here 'Page'
 	 */
 	public static void linkAll(String key,String value){
 
 		OrientGraph graph = Connections.getInstance().getDbGraph();
 		String result="";
 		int inLinks;
 		
 		//Iterating on every vertex to check it's backlinks
 		
 		for (Vertex pageNode : graph.getVertices(key,value)) {
 			
 			//Getting the JSON formatted String to process.
 			result=getBacklinks((int)(pageNode.getProperty("pid")));	
 			inLinks=0;
 			
 			//JSON interpretation of the fetched String
 			
 			 try {  
 				 	JSONObject js=new JSONObject(result);
 				 	JSONObject js2=js.getJSONObject("query");
 				 	//This array has all the backlinks the page has.
 				 	JSONArray arr=js2.getJSONArray("backlinks");	
 				 	JSONObject currentJsonObject;							
 				 	inLinks=arr.length();
 				 	
 				 	System.out.println(pageNode.getProperty("title").toString()+" has inLinks = "+inLinks);
 				 	
 				 	//Iterating to get all the backlinks of a particular node(Page)
 				 	
 				 	for(int i=0;i<arr.length();i++){
 				 		currentJsonObject=arr.getJSONObject(i);
 				 		
-				 		try{	
-				 			
+				 		try{
+				 			//The check is done to prevent the rollback in case any error occurs due to null vertices
+				 			if(graph.getVertices("pid",currentJsonObject.getInt("pageid")).iterator().hasNext()){
 				 			//Getting the node linked to the current page.
 				 			Vertex backLink=graph.getVertices("pid",currentJsonObject.getInt("pageid")).iterator().next();	
 				 			//Creating Edge in between the 2 vertices.
 				 			Edge isbackLink = graph.addEdge("Backlink", backLink, pageNode, "Backlink");				
 				 			
 				 			System.out.println(pageNode.getProperty("title").toString()+" is linked to "+backLink.getProperty("title").toString());
 				 			
-				 		graph.commit();														
+				 		graph.commit();	
+				 			}
 				 		} catch( Exception e ) {
 				 			e.printStackTrace();
 				 			//In case the transaction fails we will rollback.
 				 			graph.rollback();																	
 				 		}
 				 		
 				 	}
 			 } catch (JSONException e) { 
 				 e.printStackTrace();
 			 }
 			 
 		}
 		//graph.commit();	
 		graph.shutdown();
 		//Revision.getAllRevisions();
 	}
 					
 	
 	
 	
 	/**
 	 * This method will return the a JSON formatted string queried
 	 * from the MediaWiki API to get all the backlinking pages
 	 * @param pid	PageID of the page whose backlinks are to be fetched
 	 * @return	A JSON formatted String containing all the backlinks  
 	 */
 	public static String getBacklinks(int pid) {
 		  
 		
 		String result = "";
 		ApiConnection con=Connections.getInstance().getApiConnection();
 		//Getting the InputStream object having JSON form MediaWiki API
 		InputStream in=WikiUtil.reqSend(con,WikiUtil.getLinkParam(pid+""));	
 		//Converting the InputStream to String
 		result=WikiUtil.streamToString(in);		  							
 		return result;
 		  
 	}
 	
 }
diff --git a/WikiRating/src/main/java/utilities/AllowedNamespaces.java b/WikiRating/src/main/java/utilities/AllowedNamespaces.java
index ec9e472..5cbbeab 100644
--- a/WikiRating/src/main/java/utilities/AllowedNamespaces.java
+++ b/WikiRating/src/main/java/utilities/AllowedNamespaces.java
@@ -1,35 +1,35 @@
 package main.java.utilities;
 /**
  * This enum is the filter for the namespaces
  */
 public enum AllowedNamespaces {
 	
 
 			MAIN(0),
 			TALK(1),
 			USER(2),
 			USER_TALK(3),
 			PROJECT(4),
 			PROJECT_TALK(5),
 //			FILE(6),
 //			FILE_TALK(7),
 //			MEDIAWIKI(8),
 //			MEDIAWIKI_TALK(9),
 //			TEMPLATE(10),
 //			TEMPLATE_TALK(11),
 			HELP(12),
 			HELP_TALK(13),
 			CATEGORY(14),
-			CATEGORY_TALK(15),
-			SPECIAL(-1),
-			MEDIA(-2);
+			CATEGORY_TALK(15);
+//			SPECIAL(-1),
+//			MEDIA(-2);
 	 
 	    private  int value;
 	 
 	    AllowedNamespaces(int value) { this.value = value; }
 	 
 	    public int getValue() { return value; }
 	
 	 
 	  }