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diff --git a/src/Chapter4/util/TweetFileToGraph.java b/src/Chapter4/util/TweetFileToGraph.java
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+++ b/src/Chapter4/util/TweetFileToGraph.java
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+package Chapter4.util;
+
+import java.io.File;
+
+import GraphElements.RetweetEdge;
+import GraphElements.UserNode;
+
+import edu.uci.ics.jung.graph.DirectedGraph;
+import edu.uci.ics.jung.graph.DirectedSparseGraph;
+import edu.uci.ics.jung.graph.util.EdgeType;
+import java.util.logging.Level;
+import java.util.logging.Logger;
+import org.json.JSONException;
+import org.json.JSONObject;
+
+/**
+ *	Some basic functionality to convert files collected 
+ *	in Chapter 2 to JUNG graphs.
+ */
+public class TweetFileToGraph {
+	
+	public static DirectedGraph<UserNode, RetweetEdge> getRetweetNetwork(File tweetFile){
+		
+		JSONObject tmp;
+		
+		TweetFileProcessor tfp = new TweetFileProcessor(tweetFile);
+		DirectedSparseGraph<UserNode, RetweetEdge> dsg = new DirectedSparseGraph<UserNode, RetweetEdge>();
+		
+		while (tfp.hasNext()){
+			tmp = tfp.next();
+                        if(tmp==null)
+                        {
+                            continue;
+                        }
+			//get the author
+			String user=null;
+                        try {
+                            user = tmp.getJSONObject("user").getString("screen_name");
+                        } catch (JSONException ex) {
+                            Logger.getLogger(TweetFileToGraph.class.getName()).log(Level.SEVERE, null, ex);
+                        }
+			if(user==null)
+                        {
+                            continue;
+                        }
+			//get the retweeted user
+			try{
+				JSONObject retweet = tmp.getJSONObject("retweeted_status");
+				String retweeted_user = retweet.getJSONObject("user").getString("screen_name");
+				
+				//make an edge or increment the weight if it exists.
+				UserNode toUser = new UserNode(retweeted_user);
+				UserNode fromUser = new UserNode(user);
+				
+				dsg.addVertex(toUser);
+				dsg.addVertex(fromUser);
+			
+				RetweetEdge edge = new RetweetEdge(toUser, fromUser); 
+				
+				if(dsg.containsEdge(edge)){
+					dsg.findEdge(fromUser, toUser).incrementRTCount();
+				}
+				else{
+					dsg.addEdge(edge, fromUser, toUser);
+				}
+				dsg.addEdge(edge, fromUser, toUser, EdgeType.DIRECTED);
+			}
+			catch(JSONException ex){
+				//the tweet is not a retweet. this is not a problem.
+			}
+			
+			
+		}
+		
+		return dsg;
+	}
+}