TweetCollector.DBManager.java Source code

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Here is the source code for TweetCollector.DBManager.java

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package TweetCollector;

import java.net.UnknownHostException;
import java.util.Map.Entry;
import java.util.Set;
import java.util.logging.Level;
import java.util.logging.Logger;

import twitter4j.Trend;
import TweetCollector.TrendList.TrendData;

import com.mongodb.BasicDBObject;
import com.mongodb.DB;
import com.mongodb.DBCollection;
import com.mongodb.DBObject;
import com.mongodb.Mongo;
import com.mongodb.MongoURI;
import com.mongodb.util.JSON;

/**
 *
 * @author george
 */
public class DBManager {

    private static DB db;
    private static DBCollection tweetsCollection;
    private static DBCollection trendsCollection;

    public DBManager() {
        this("mongodb://localhost:28888");
    }

    @SuppressWarnings("deprecation")
    public DBManager(String conStr) {

        // create the database
        try {
            // make the initial connection to the mongoDB
            Mongo tweetsMongoClient = new Mongo(new MongoURI(conStr));
            DBManager.db = tweetsMongoClient.getDB("twitter_mini");
        } catch (UnknownHostException ex) {
            System.err.println("The database could not be initialized because of an UnknownHostException.");
            Logger.getLogger(DBManager.class.getName()).log(Level.SEVERE, null, ex);
        }

        // create the tweets collection
        DBManager.tweetsCollection = DBManager.db.getCollection("tweets");
        // tweetsCollection.ensureIndex(new BasicDBObject("text", "text"));

        // create the trends collection
        DBManager.trendsCollection = DBManager.db.getCollection("trends");
    }

    // update( {"name": name}, {"$addToSet" : { "activity_times": time } },
    // {"upsert": true});
    // Inserts trend if it doesn't exist in db, else simply inser the new
    // activity time
    // (end times can be calculated using this info alone)
    public void insertTrends(Set<Entry<Trend, TrendData>> trends) {
        for (Entry<Trend, TrendData> e : trends) {

            BasicDBObject query = new BasicDBObject("name", e.getKey().getName());
            BasicDBObject op = new BasicDBObject("$addToSet",
                    new BasicDBObject("activity_times", e.getValue().time.getTime()));

            db.getCollection("trends").update(query, op, true, false);
        }
    }

    /*
     * public void insertTrends(String json) {
     * 
     * //parse the json with the current trends DBObject ob = (DBObject)
     * JSON.parse(json);
     * 
     * //get the date of the current trends json file String
     * dateString=(String)ob.get("as_of");
     * 
     * //store the trends in a list BasicDBList trends = (BasicDBList)
     * ob.get("trends");
     * 
     * for(Object trend : trends){ DBObject t = (DBObject) trend;
     * 
     * //get the name of the trend String name=(String) t.get("name");
     * 
     * BasicDBObject query = new BasicDBObject(); ArrayList<BasicDBObject> obj =
     * new ArrayList<BasicDBObject>(); obj.add(new BasicDBObject("name", name));
     * obj.add(new BasicDBObject("off_date", null)); query.put("$and", obj);
     * DBCursor cursor = trendsCollection.find(query);
     * 
     * //check to see if it's a- running hot trend or not if(!cursor.hasNext()){
     * BasicDBObject newTrend = new BasicDBObject("name",name).append("on_date",
     * dateString).append("off_date", null); trendsCollection.insert(newTrend);
     * }
     * 
     * }
     * 
     * //now check if some trends should be considered as not running from now
     * on BasicDBObject query = new BasicDBObject(); ArrayList<String> list =
     * new ArrayList<>(); for(Object trend : trends){ DBObject t = (DBObject)
     * trend; list.add((String) t.get("name")); } ArrayList<BasicDBObject> obj =
     * new ArrayList<BasicDBObject>(); obj.add(new BasicDBObject("name", new
     * BasicDBObject("$nin", list))); obj.add(new BasicDBObject("off_date",
     * null)); query.put("$and", obj);
     * 
     * //for every such document update its off_date to the current date
     * BasicDBObject newDocument = new BasicDBObject().append("$set", new
     * BasicDBObject().append("off_date", dateString));
     * trendsCollection.update(query, newDocument); }
     */

    public void insertTweet(String json) {
        DBObject ob = (DBObject) JSON.parse(json);

        tweetsCollection.insert(ob);
    }

    public static long tweetCount() {
        return tweetsCollection.getCount();

    }

    public DBCollection getTweets() {
        return tweetsCollection;
    }
}