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diff --git a/src/Chapter5/trends/ExtractDatasetTrend.java b/src/Chapter5/trends/ExtractDatasetTrend.java
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+/* TweetTracker. Copyright (c) Arizona Board of Regents on behalf of Arizona State University
+ * @author shamanth
+ */
+package Chapter5.trends;
+
+import java.io.BufferedReader;
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.IOException;
+import java.io.InputStreamReader;
+import java.text.ParseException;
+import java.text.SimpleDateFormat;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.Date;
+import java.util.HashMap;
+import java.util.Set;
+import java.util.logging.Level;
+import java.util.logging.Logger;
+import org.json.JSONArray;
+import org.json.JSONException;
+import org.json.JSONObject;
+
+public class ExtractDatasetTrend
+{
+    static final String DEF_INFILENAME = "ows.json";
+    // Date pattern used to count the volume of tweets
+    final SimpleDateFormat SDM = new SimpleDateFormat("dd MMM yyyy HH:mm");
+
+    public JSONArray GenerateDataTrend(String inFilename)
+    {
+        BufferedReader br = null;
+        JSONArray result = new JSONArray();
+        HashMap<String,Integer> datecount = new HashMap<String,Integer>();
+        try{
+            br= new BufferedReader(new InputStreamReader(new FileInputStream(inFilename),"UTF-8"));
+            String temp = "";
+            while((temp = br.readLine())!=null)
+            {
+                try {
+                    JSONObject jobj = new JSONObject(temp);
+                    long timestamp = jobj.getLong("timestamp");
+                    Date d = new Date(timestamp);
+                    String strdate = SDM.format(d);
+                    if(datecount.containsKey(strdate))
+                    {
+                        datecount.put(strdate, datecount.get(strdate)+1);
+                    }
+                    else
+                    {
+                        datecount.put(strdate, 1);
+                    }
+                } catch (JSONException ex) {
+                    Logger.getLogger(ExtractDatasetTrend.class.getName()).log(Level.SEVERE, null, ex);
+                }                
+            }
+            /** DateInfo consists of a date string and the corresponding count.
+              * It also implements a Comparator for sorting by date
+              */
+            ArrayList<DateInfo> dinfos = new ArrayList<DateInfo>();
+            Set<String> keys = datecount.keySet();
+            for(String key:keys)
+            {
+                DateInfo dinfo = new DateInfo();
+                try {
+                    dinfo.d = SDM.parse(key);
+                } catch (ParseException ex) {
+                    ex.printStackTrace();
+                    continue;
+                }
+                dinfo.count = datecount.get(key);
+                dinfos.add(dinfo);
+            }
+            Collections.sort(dinfos);
+            // Format and return the date string and the corresponding count
+            for(DateInfo dinfo:dinfos)
+            {
+                try{
+                    JSONObject jobj = new JSONObject();
+                    jobj.put("date", SDM.format(dinfo.d));
+                    jobj.put("count", dinfo.count);
+                    result.put(jobj);
+                }catch(JSONException ex)
+                {
+                    ex.printStackTrace();
+                }
+            }
+        }catch(IOException ex)
+        {
+            ex.printStackTrace();
+        }finally{
+            try {
+                br.close();
+            } catch (IOException ex) {
+                Logger.getLogger(ExtractDatasetTrend.class.getName()).log(Level.SEVERE, null, ex);
+            }
+        }
+        return result;
+    }
+
+    public static void main(String[] args)
+    {
+        ExtractDatasetTrend edt = new ExtractDatasetTrend();
+        
+        String infilename = DEF_INFILENAME;
+        if(args!=null)
+        {
+            if(args.length>=1&&!args[0].isEmpty())
+            {
+                File fl = new File(args[0]);
+                if(fl.exists())
+                {
+                    infilename = args[0];
+                }
+            }
+        }
+        System.out.println(edt.GenerateDataTrend(infilename));
+    }
+
+}