swm.project.loadDataToDb.GetDataFromDb.java Source code

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Here is the source code for swm.project.loadDataToDb.GetDataFromDb.java

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package swm.project.loadDataToDb;

import com.mongodb.BasicDBObject;
import com.mongodb.DBCursor;
import com.mongodb.DBObject;
import com.mongodb.MongoClient;
import com.mongodb.client.FindIterable;
import com.mongodb.client.MongoCollection;
import com.mongodb.client.MongoCursor;
import com.mongodb.client.MongoDatabase;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import org.bson.Document;
import swm.project.Consts;
import org.bson.types.ObjectId;

/**
 *
 * @author Kruti
 */
public class GetDataFromDb {
    MongoClient mongoClient;
    MongoDatabase db;

    public GetDataFromDb() {
        connectToDb();
    }

    private void connectToDb() {
        mongoClient = new MongoClient("localhost", 27017);
        db = mongoClient.getDatabase(Consts.DBNAME);
    }

    /**
     * 
     * @return 
     * returns : HashMap<Integer, HashMap<Integer, Integer>>
     * i.e. HashMap<userid, HashMap<movieId, rating>>
     */
    public HashMap<Integer, HashMap<Integer, Integer>> getAllUserRatings() {
        MongoCollection<Document> collection;
        collection = db.getCollection(Consts.UDATA);
        HashMap<Integer, HashMap<Integer, Integer>> userRatings = new HashMap<>();
        FindIterable<Document> userRatingData = collection.find();
        MongoCursor<Document> userRatingCursor = userRatingData.iterator();
        while (userRatingCursor.hasNext()) {
            Document ratingFields = userRatingCursor.next();
            int userId = (int) ratingFields.get("userid");
            int movieId = (int) ratingFields.get("itemid");
            int rating = (int) ratingFields.get("rating");

            if (userRatings.containsKey(userId)) {
                HashMap<Integer, Integer> itemRatings = userRatings.get(userId);
                itemRatings.put(movieId, rating);
            } else {
                HashMap<Integer, Integer> itemRatings = new HashMap<Integer, Integer>();
                itemRatings.put(movieId, rating);
                userRatings.put(userId, itemRatings);
            }
        }
        return userRatings;
    }

    public List<String> getMovieDetails(List<Integer> movieID) {
        MongoCollection<Document> movieNamesCollection = db.getCollection(Consts.MOVIE_NAME_DATA);
        //FindIterable<Document> movieNamesAll = movieNamesCollection.find();
        //MongoCursor movieNamesCursorX = movieNamesAll.iterator();
        ArrayList<String> names = new ArrayList<>();
        BasicDBObject whereQuery = new BasicDBObject();
        for (int i = 0; i < movieID.size(); i++) {
            whereQuery.put("_id", movieID.get(i));
            FindIterable<Document> iterate = movieNamesCollection.find(whereQuery);
            MongoCursor cursor = iterate.iterator();
            while (cursor.hasNext()) {
                Document ratingFields = (Document) cursor.next();
                String movieName = (String) ratingFields.get(Consts.MOVIE_NAME_FIELD);
                //System.out.println(movieName);          
                names.add(movieName);
            }
        }
        return names;
    }
}