TweetAnalytics.DBManager.java Source code

Introduction

Here is the source code for TweetAnalytics.DBManager.java

Source

/*
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package TweetAnalytics;

import java.net.UnknownHostException;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Calendar;
import java.util.List;
import java.util.Random;
import java.util.logging.Level;
import java.util.logging.Logger;

import twitter4j.api.TweetsResources;

import com.mongodb.AggregationOptions;
import com.mongodb.BasicDBList;
import com.mongodb.BasicDBObject;
import com.mongodb.Cursor;
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 avail
 */
public class DBManager {

    private static DB db;

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

    public DBManager(String conStr) {

        // create the database
        try {
            // make the initial connection to the mongoDB
            @SuppressWarnings("deprecation")
            Mongo tweetsMongoClient = new Mongo(new MongoURI(conStr));
            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);
        }
    }

    public long[] fetchChosenUsers(String col) {
        long[] user_ids = new long[(int) db.getCollection(col).count()];
        Cursor cursor = db.getCollection(col).find();
        int i = 0;
        while (cursor.hasNext()) {
            DBObject e = cursor.next();
            if (e.get("_id") instanceof Long)
                user_ids[i++] = (Long) e.get("_id");
            else if (e.get("_id") instanceof Integer)
                user_ids[i++] = ((Integer) e.get("_id")).longValue();
        }
        return user_ids;
    }

    //public DBCollection getTweets() {
    //   return db.getCollection("tweets");
    //}

    public void insertDoc(String col, String json) {
        DBObject ob = (DBObject) JSON.parse(json);
        db.getCollection(col).insert(ob);
    }

    public long tweetCount() {
        return db.getCollection("chosen_user_tweets").getCount();
    }

    @SuppressWarnings("deprecation")
    public void initUserCollection(String usr_col) {
        if (db.collectionExists(usr_col))
            //throw new RuntimeException(
            System.out.println("Mongo: Users collection already exists.");

        db.getCollection(usr_col).drop();
        db.getCollection(usr_col).ensureIndex(new BasicDBObject("tweets", "text"));
    }

    public DBCollection getCollection(String collection) {
        return db.getCollection(collection);
    }

    public boolean exists(String collection) {
        return db.collectionExists(collection);
    }

}