Java Code Examples for com.mongodb.MongoClient#getDatabase()

public MongoDocumentStorage(MongoClient mongoClient, String indexName, String dbName, String rawCollectionName, boolean sharded) {
	this.mongoClient = mongoClient;
	this.indexName = indexName;
	this.database = dbName;
	this.rawCollectionName = rawCollectionName;

	MongoDatabase storageDb = mongoClient.getDatabase(database);
	MongoCollection<Document> coll = storageDb.getCollection(ASSOCIATED_FILES + "." + FILES);
	coll.createIndex(new Document(ASSOCIATED_METADATA + "." + DOCUMENT_UNIQUE_ID_KEY, 1));
	coll.createIndex(new Document(ASSOCIATED_METADATA + "." + FILE_UNIQUE_ID_KEY, 1));

	if (sharded) {

		MongoDatabase adminDb = mongoClient.getDatabase(MongoConstants.StandardDBs.ADMIN);
		Document enableCommand = new Document();
		enableCommand.put(MongoConstants.Commands.ENABLE_SHARDING, database);
		adminDb.runCommand(enableCommand);

		shardCollection(storageDb, adminDb, rawCollectionName);
		shardCollection(storageDb, adminDb, ASSOCIATED_FILES + "." + CHUNKS);
	}
}
 

/**
 * Connect MongoDB and call callback, close connection at last.
 *
 * @param collectionName Collection name.
 * @param callback       Callback
 * @param <T>            The type of value which you want to return.
 * @return The value which callback returned.
 */
public <T> T connect(String collectionName, CollectionCallback<T> callback) {
  MongoClient client = null;
  T t = null;
  try {
    client = getConnectedClient();
    MongoDatabase database = client.getDatabase(databaseName);
    MongoCollection<Document> collection = database.getCollection(collectionName);
    t = callback.doInCollection(collection);
  } finally {
    if (client != null) {
      client.close();
    }
  }
  return t;
}
 

@Override
public void start(Map<String, String> props) {
    LOGGER.info("starting MongoDB sink task");

    sinkConfig = new MongoDbSinkConnectorConfig(props);

    MongoClientURI uri = sinkConfig.buildClientURI();
    mongoClient = new MongoClient(uri);
    database = mongoClient.getDatabase(uri.getDatabase());

    remainingRetries = sinkConfig.getInt(
            MongoDbSinkConnectorConfig.MONGODB_MAX_NUM_RETRIES_CONF);
    deferRetryMs = sinkConfig.getInt(
            MongoDbSinkConnectorConfig.MONGODB_RETRIES_DEFER_TIMEOUT_CONF);

    processorChains = sinkConfig.buildPostProcessorChains();
    cdcHandlers = sinkConfig.getCdcHandlers();

    writeModelStrategies = sinkConfig.getWriteModelStrategies();
    rateLimitSettings = sinkConfig.getRateLimitSettings();
    deleteOneModelDefaultStrategies = sinkConfig.getDeleteOneModelDefaultStrategies();

}
 

private void setMongoDB(JSONObject json) {
	if (json.isNull("backend_ip")) {
		backend_ip = "localhost";
	} else {
		backend_ip = json.getString("backend_ip");
	}
	if (json.isNull("backend_port")) {
		backend_port = 27017;
	} else {
		backend_port = json.getInt("backend_port");
	}
	if (json.isNull("backend_database_name")) {
		databaseName = "epcis";
	} else {
		databaseName = json.getString("backend_database_name");
	}
	mongoClient = new MongoClient(backend_ip, backend_port);
	mongoDatabase = mongoClient.getDatabase(databaseName);

	persistentGraph = new ChronoGraph(backend_ip, backend_port, databaseName);
	persistentGraphData = new ChronoGraph(backend_ip, backend_port, databaseName + "-data");
}
 

public static MongoDatabase getMongoDatabase( Properties connProperties ) throws OdaException
{
       MongoClient mongoClient = MongoDBDriver.getMongoNode( connProperties );        
       
       // to avoid potential conflict in shared DB, ReadPreference is exposed
       // as cursorReadPreference in data set property
       
       String dbName = MongoDBDriver.getDatabaseName( connProperties );
       if( dbName == null || dbName.isEmpty() )
           throw new OdaException( Messages.mDbConnection_missingValueDBName );
	
	MongoDatabase dbInstance = null;
       try
	{
		Boolean dbExists = existsDatabase( mongoClient, dbName, connProperties );
		if( dbExists != null && !dbExists  )    // does not exist for sure
		{
			// do not proceed to create new database instance
			 throw new OdaException( 
					 Messages.bind( Messages.mDbConnection_invalidDatabaseName, dbName )); 
		}

		dbInstance = mongoClient.getDatabase( dbName );
		authenticateDB( dbInstance, connProperties );
	}
	catch ( Exception ex )
	{
		MongoDBDriver.getLogger( ).log( Level.SEVERE,
				"Unable to get Database "
						+ dbName + ". " + ex.getMessage( ),
				ex );
		throw new OdaException( ex );
	}	
       return dbInstance;	    
}
 

@Override
public void beforeTest(final TestInvocation invocation) throws Exception {
    final ExecutionContext context = invocation.getContext();

    final Configuration configuration = configurationRegistry.getConfiguration(context.getDescriptor());

    final MongoClient client = (MongoClient) context.getData(Constants.KEY_MONGO_CLIENT);
    final MongoDatabase mongoDb = client.getDatabase(configuration.getDatabaseName());
    context.storeData(Constants.KEY_MONGO_DB, mongoDb);

    final MongoDbFeatureExecutor dbFeatureExecutor = new MongoDbFeatureExecutor(invocation.getFeatureResolver());

    dbFeatureExecutor.executeBeforeTest(mongoDb);
    context.storeData(Constants.KEY_FEATURE_EXECUTOR, dbFeatureExecutor);
}
 

private long getEstimatedSizeBytes(
    MongoClient mongoClient, String database, String collection) {
  MongoDatabase mongoDatabase = mongoClient.getDatabase(database);

  // get the Mongo collStats object
  // it gives the size for the entire collection
  BasicDBObject stat = new BasicDBObject();
  stat.append("collStats", collection);
  Document stats = mongoDatabase.runCommand(stat);

  return stats.get("size", Number.class).longValue();
}
 

@Override
public void init(ZeppelinConfiguration zConf) throws IOException {
  this.conf = zConf;
  client = new MongoClient(new MongoClientURI(conf.getMongoUri()));
  db = client.getDatabase(conf.getMongoDatabase());
  notes = db.getCollection(conf.getMongoCollection());
  folderName = conf.getMongoFolder();
  folders = db.getCollection(folderName);

  if (conf.getMongoAutoimport()) {
    // import local notes into MongoDB
    insertFileSystemNotes();
  }
}
 

/**
 * Starts the {@link Mongo} instance and explicitly checks whether it is
 * actually alive.
 *
 * @throws PersistenceStartException if we can't make a connection to MongoDb.
 */
private void start() {
  Preconditions.checkState(!isRunning(), "Can't start after a connection has been established");

  String host = dbHost;
  int port = Integer.parseInt(dbPort);
  mongoClient = new MongoClient(host, port);

  MongoDatabase database = mongoClient.getDatabase(dbName);

  isRunning = true;
  LOG.info("Started MongoDb persistence");
}
 

public static void main(String args[]) {

        ConsoleLogger cl = new ConsoleLogger("test");

        cl.setDebugable(true);

        UAVServer.instance().setLog(cl);

        UAVServer.instance().putServerInfo(CaptureConstants.INFO_APPSERVER_VENDOR, ServerVendor.TOMCAT);

        MongoClientHookProxy p = new MongoClientHookProxy("test", Collections.emptyMap());

        p.doInstallDProxy(null, "testApp");

        MongoClient client = new MongoClient();
        client.listDatabaseNames().first();
        MongoDatabase db = client.getDatabase("apphubDataStore");
        db.listCollectionNames().first();
        MongoCollection<Document> collection = db.getCollection("test");
        collection.listIndexes().first();
        Document doc = new Document("name", "Amarcord Pizzeria")
                .append("contact",
                        new Document("phone", "264-555-0193").append("email", "[email protected]")
                                .append("location", Arrays.asList(-73.88502, 40.749556)))
                .append("stars", 2).append("categories", Arrays.asList("Pizzeria", "Italian", "Pasta"));
        collection.insertOne(doc);
        collection.find().first();

        MongoClient client2 = new MongoClient("localhost:27017");
        db = client2.getDatabase("apphubDataStore");
        db.listCollectionNames().first();
        collection = db.getCollection("test");
        collection.listIndexes().first();

        client.close();
        client2.close();
    }
 

/**
 * Creates a MongoDB schema.
 *
 * @param host Mongo host, e.g. "localhost"
 * @param credential Optional credentials (null for none)
 * @param options Mongo connection options
 * @param database Mongo database name, e.g. "foodmart"
 */
MongoSchema(String host, String database,
    MongoCredential credential, MongoClientOptions options) {
  super();
  try {
    final MongoClient mongo = credential == null
        ? new MongoClient(new ServerAddress(host), options)
        : new MongoClient(new ServerAddress(host), credential, options);
    this.mongoDb = mongo.getDatabase(database);
  } catch (Exception e) {
    throw new RuntimeException(e);
  }
}
 

public void test() throws IOException, InterruptedException {

		File file = new File(fileBaseLoc + this.getClass().getSimpleName() + "-cache-bfs");
		file.createNewFile();
		FileWriter fw = new FileWriter(file);
		BufferedWriter bw = new BufferedWriter(fw);

		String baseEPC = "urn:epc:id:sgtin:0000001.000001.";

		MongoClient client = new MongoClient();
		MongoDatabase db = client.getDatabase("test1");
		db.getCollection("edges").drop();
		db.getCollection("vertices").drop();
		db.getCollection("edges").createIndex(new BsonDocument("_outV", new BsonInt32(1))
				.append("_label", new BsonInt32(1)).append("_t", new BsonInt32(1)).append("_inV", new BsonInt32(1)));
		client.close();

		ChronoGraph g = new ChronoGraph("test1");

		for (int i = 0; i < transferCount; i++) {

			long cTime = System.currentTimeMillis();
			g.addTimestampEdgeProperties(baseEPC + i, baseEPC + (2 * i + 1), "transformTo", cTime, new BsonDocument());
			g.addTimestampEdgeProperties(baseEPC + i, baseEPC + (2 * i + 2), "transformTo", cTime, new BsonDocument());

			Thread.sleep(2000);

			double avg = doTransformationQuery(g);

			System.out.println(i + "\t" + avg);
			bw.write(i + "\t" + avg + "\n");
			bw.flush();
		}
		bw.close();
	}
 

public static void main(String[] args) {
    MongoClient client = new MongoClient("localhost", 27017);
    MongoDatabase friends = client.getDatabase("friends");
    MongoCollection relatives = friends.getCollection("relatives");
    
    Bson bson = Sorts.ascending("fname");
    FindIterable<Document> docs = relatives.find().sort(bson);
    int num = 0;
    for (Document doc : docs) {
        String name = doc.getString("fname");
        String relation = doc.getString("relation");
        System.out.printf("%4d. %s, %s%n", ++num, name, relation);
    }
}
 

@PostConstruct
public void initConnection() {
    String mongoHost = env.getProperty("mongodb.server.host", "127.0.0.1"); // env var MONGODB_SERVER_HOST takes precedence
    String mongoPort = env.getProperty("mongodb.server.port", "27017"); // env var MONGODB_SERVER_PORT takes precedence
    String mongoUri = env.getProperty("uri", "");
    String mongoUser = env.getProperty("mongodb.user", "mongodb"); // env var MONGODB_USER takes precedence
    String mongoPassword = env.getProperty("mongodb.password", "mongodb"); // env var MONGODB_PASSWORD takes precedence
    String mongoDBName = env.getProperty("mongodb.database", "mongodb"); // env var MONGODB_DATABASE takes precedence
    String dbServiceName = env.getProperty("database.service.name", "");

    try {
    	// If mongoUri is set, we use this, else, we use mongoHost and mongoPort
    	// This will come in this form (mongodb://127.0.0.1:27017)
    	if (mongoUri!=null && ! "".equals(mongoUri)){
    		Pattern pattern = Pattern.compile("mongodb?://([^:^/]*):?(\\d*)?");
    		Matcher matcher = pattern.matcher(mongoUri);
    		if (matcher.find()){
    			mongoHost = matcher.group(1);
    			mongoPort = matcher.group(2);
    			// We assume all information comes in the binding format
    	        mongoUser = env.getProperty("username", "mongodb");
    	        mongoPassword = env.getProperty("password", "mongodb");
    	        mongoDBName = env.getProperty("database_name", "mongodb");       			
    		}
    	} else if (dbServiceName !=null && ! "".equals(dbServiceName)) {
            mongoHost = dbServiceName;
        }
    	
        String mongoURI = "mongodb://" + mongoUser + ":" + mongoPassword + "@" + mongoHost + ":" + mongoPort + "/" + mongoDBName;
        System.out.println("[INFO] Connection string: " + mongoURI);
        MongoClient mongoClient = new MongoClient(new MongoClientURI(mongoURI));
        mongoDB = mongoClient.getDatabase(mongoDBName);
    } catch (Exception e) {
        System.out.println("[ERROR] Creating the mongoDB. " + e.getMessage());
        mongoDB = null;
    }
}
 

public void test() throws IOException, InterruptedException {

		File file = new File(fileBaseLoc + this.getClass().getSimpleName() + "-cache-bfs");
		file.createNewFile();
		FileWriter fw = new FileWriter(file);
		BufferedWriter bw = new BufferedWriter(fw);

		MongoClient client = new MongoClient();
		MongoDatabase db = client.getDatabase("epcis");
		db.getCollection("EventData").drop();
		db.getCollection("edges").drop();
		db.getCollection("vertices").drop();
		db.getCollection("edges").createIndex(new BsonDocument("_outV", new BsonInt32(1)).append("_t", new BsonInt32(1))
				.append("_inV", new BsonInt32(1)));

		client.close();

		SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss.SSS'Z'");
		String cTime = sdf.format(new Date());

		long lastTimeMil = System.currentTimeMillis() + 100000000;

		for (int i = 0; i < transferCount; i++) {

			Thread.sleep(1000);

			cTime = sdf.format(new Date());
			String epcParent = String.format("%010d", i + 1);
			String epcChild = String.format("%010d", i);

			// urn:epc:id:sscc:0000002.0000000001

			String top = "<?xml version=\"1.0\" encoding=\"UTF-8\" standalone=\"yes\"?>\n" + "<!DOCTYPE project>\n"
					+ "<epcis:EPCISDocument schemaVersion=\"1.2\"\n"
					+ "	creationDate=\"2013-06-04T14:59:02.099+02:00\" xmlns:epcis=\"urn:epcglobal:epcis:xsd:1\"\n"
					+ "	xmlns:example=\"http://ns.example.com/epcis\">\n" + "	<EPCISBody>\n" + "		<EventList>";

			String bottom = "</EventList>\n" + "	</EPCISBody>\n" + "</epcis:EPCISDocument>";

			String body = "<AggregationEvent>\n" + "				<eventTime>" + cTime + "</eventTime>\n"
					+ "				<eventTimeZoneOffset>+00:00</eventTimeZoneOffset>\n"
					+ "				<parentID>urn:epc:id:sscc:0000001." + epcParent + "</parentID>\n"
					+ "				<childEPCs>\n" + "					<epc>urn:epc:id:sscc:0000001." + epcChild
					+ "</epc>\n" + "				</childEPCs>\n" + "				<action>ADD</action>\n"
					+ "				<bizStep>urn:epcglobal:cbv:bizstep:loading</bizStep>\n"
					+ "				<!-- TNT Liverpool depot -->\n" + "				<bizLocation>\n"
					+ "					<id>urn:epc:id:sgln:0000001.00002.1</id>\n" + "				</bizLocation>\n"
					+ "			</AggregationEvent>";

			String lastTime = sdf.format(new Date(lastTimeMil - i));

			body += "<AggregationEvent>\n" + "				<eventTime>" + lastTime + "</eventTime>\n"
					+ "				<eventTimeZoneOffset>+00:00</eventTimeZoneOffset>\n"
					+ "				<parentID>urn:epc:id:sscc:0000001." + epcParent + "</parentID>\n"
					+ "				<childEPCs>\n" + "					<epc>urn:epc:id:sscc:0000001." + epcChild
					+ "</epc>\n" + "				</childEPCs>\n" + "				<action>DELETE</action>\n"
					+ "				<bizStep>urn:epcglobal:cbv:bizstep:loading</bizStep>\n"
					+ "				<!-- TNT Liverpool depot -->\n" + "				<bizLocation>\n"
					+ "					<id>urn:epc:id:sgln:0000001.00002.1</id>\n" + "				</bizLocation>\n"
					+ "			</AggregationEvent>";

			EventCapture cap = new EventCapture();
			cap.capture(top + body + bottom);

			Thread.sleep(3000);

			int avg = doTransformationQuery();

			System.out.println(i + "\t" + avg);
			bw.write(i + "\t" + avg + "\n");
			bw.flush();
		}
		bw.close();
	}
 

public void test()
		throws IOException, InterruptedException, ParserConfigurationException, SAXException, ParseException {

	File file = new File(fileBaseLoc + this.getClass().getSimpleName() + "-cache-bfs");
	file.createNewFile();
	FileWriter fw = new FileWriter(file);
	BufferedWriter bw = new BufferedWriter(fw);

	MongoClient client = new MongoClient();
	MongoDatabase db = client.getDatabase("epcis");
	db.getCollection("EventData").drop();
	db.getCollection("edges").drop();
	db.getCollection("vertices").drop();
	db.getCollection("edges").createIndex(new BsonDocument("_outV", new BsonInt32(1)).append("_t", new BsonInt32(1))
			.append("_inV", new BsonInt32(1)));

	client.close();

	for (int i = 0; i < transferCount; i++) {

		// Insert Event
		String top = "<?xml version=\"1.0\" encoding=\"UTF-8\" standalone=\"yes\"?>\n" + "<!DOCTYPE project>\n"
				+ "<epcis:EPCISDocument schemaVersion=\"1.2\"\n"
				+ "	creationDate=\"2013-06-04T14:59:02.099+02:00\" xmlns:epcis=\"urn:epcglobal:epcis:xsd:1\"\n"
				+ "	xmlns:example=\"http://ns.example.com/epcis\">\n" + "	<EPCISBody>\n" + "		<EventList>";

		String bottom = "</EventList>\n" + "	</EPCISBody>\n" + "</epcis:EPCISDocument>";

		SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss.SSS'Z'");
		String cTime = sdf.format(new Date());

		String body = "";

		Thread.sleep(1000);

		cTime = sdf.format(new Date());

		body += "<ObjectEvent>\n" + "	<eventTime>" + cTime + "</eventTime>\n"
				+ "	<eventTimeZoneOffset>+00:00</eventTimeZoneOffset>\n" + "	<epcList>\n"
				+ "		<epc>urn:epc:id:sgtin:0000001.000001.0</epc>\n" + "	</epcList>\n"
				+ "	<action>OBSERVE</action>\n" + "	<bizStep>urn:epcglobal:cbv:bizstep:receiving</bizStep>\n"
				+ "	<bizLocation>\n" + "		<id>urn:epc:id:sgln:0000001.00001." + i + "</id>\n"
				+ "	</bizLocation>\n" + "</ObjectEvent>";

		EventCapture cap = new EventCapture();
		cap.capture(top + body + bottom);

		Thread.sleep(1000);

		double avg = doTransformationQuery();

		System.out.println(i + "\t" + avg);
		bw.write(i + "\t" + avg + "\n");
		bw.flush();
	}
	bw.close();
}
 

public void test() throws IOException, InterruptedException {

		File file = new File(fileBaseLoc + this.getClass().getSimpleName() + "-cache-bfs");
		file.createNewFile();
		FileWriter fw = new FileWriter(file);
		BufferedWriter bw = new BufferedWriter(fw);

		MongoClient client = new MongoClient();
		MongoDatabase db = client.getDatabase("epcis");
		db.getCollection("EventData").drop();
		db.getCollection("edges").drop();
		db.getCollection("vertices").drop();
		db.getCollection("tEdgeEvents").drop();
		db.getCollection("tVertexEvents").drop();
		MongoDatabase db2 = client.getDatabase("epcis-data");
		db2.getCollection("vertices").drop();
		client.close();

		for (int i = 0; i < transferCount; i++) {

			// Insert Event
			String top = "<?xml version=\"1.0\" encoding=\"UTF-8\" standalone=\"yes\"?>\n" + "<!DOCTYPE project>\n"
					+ "<epcis:EPCISDocument schemaVersion=\"1.2\"\n"
					+ "	creationDate=\"2013-06-04T14:59:02.099+02:00\" xmlns:epcis=\"urn:epcglobal:epcis:xsd:1\"\n"
					+ "	xmlns:example=\"http://ns.example.com/epcis\">\n" + "	<EPCISBody>\n" + "		<EventList>";

			String bottom = "</EventList>\n" + "	</EPCISBody>\n" + "</epcis:EPCISDocument>";

			SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss.SSS'Z'");
			String cTime = sdf.format(new Date());

			String body = "";

			cTime = sdf.format(new Date());
			body += "<extension>\n" + "				<TransformationEvent>\n" + "					<eventTime>" + cTime
					+ "</eventTime>\n" + "					<eventTimeZoneOffset>+00:00</eventTimeZoneOffset>\n"
					+ "					<inputEPCList>\n"
					+ "						<epc>urn:epc:id:sgtin:0000001.000001." + i + "</epc>\n"
					+ "					</inputEPCList>\n" + "					<outputEPCList>\n"
					+ "						<epc>urn:epc:id:sgtin:0000001.000001." + (2 * i + 1) + "</epc>\n"
					+ "						<epc>urn:epc:id:sgtin:0000001.000001." + (2 * i + 2) + "</epc>\n"
					+ "					</outputEPCList>\n" + "				</TransformationEvent>\n"
					+ "			</extension>";
			EventCapture cap = new EventCapture();
			cap.capture(top + body + bottom);

			Thread.sleep(2000);

			int length = doTransformationQuery();

			System.out.println(i + "\t" + length);
			bw.write(i + "\t" + length + "\n");
			bw.flush();
		}
		bw.close();
	}
 

public void test() throws IOException, InterruptedException {

		File file = new File(fileBaseLoc + this.getClass().getSimpleName() + "-cache-bfs");
		file.createNewFile();
		FileWriter fw = new FileWriter(file);
		BufferedWriter bw = new BufferedWriter(fw);

		MongoClient client = new MongoClient();
		MongoDatabase db = client.getDatabase("epcis");
		db.getCollection("EventData").drop();
		db.getCollection("edges").drop();
		db.getCollection("vertices").drop();
		db.getCollection("edges").createIndex(new BsonDocument("_outV", new BsonInt32(1)).append("_t", new BsonInt32(1))
				.append("_inV", new BsonInt32(1)));

		client.close();

		for (int i = 0; i < transferCount; i++) {

			// Insert Event
			String top = "<?xml version=\"1.0\" encoding=\"UTF-8\" standalone=\"yes\"?>\n" + "<!DOCTYPE project>\n"
					+ "<epcis:EPCISDocument schemaVersion=\"1.2\"\n"
					+ "	creationDate=\"2013-06-04T14:59:02.099+02:00\" xmlns:epcis=\"urn:epcglobal:epcis:xsd:1\"\n"
					+ "	xmlns:example=\"http://ns.example.com/epcis\">\n" + "	<EPCISBody>\n" + "		<EventList>";

			String bottom = "</EventList>\n" + "	</EPCISBody>\n" + "</epcis:EPCISDocument>";

			SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss.SSS'Z'");
			String cTime = sdf.format(new Date());

			String body = "";

			Thread.sleep(1000);

			cTime = sdf.format(new Date());

			body += "<ObjectEvent>\n" + "	<eventTime>" + cTime + "</eventTime>\n"
					+ "	<eventTimeZoneOffset>+00:00</eventTimeZoneOffset>\n" + "	<epcList>\n"
					+ "		<epc>urn:epc:id:sgtin:0000001.000001.0</epc>\n" + "	</epcList>\n"
					+ "	<action>OBSERVE</action>\n" + "	<bizStep>urn:epcglobal:cbv:bizstep:receiving</bizStep>\n"
					+ "	<bizLocation>\n" + "		<id>urn:epc:id:sgln:0000001.00001." + i + "</id>\n"
					+ "	</bizLocation>\n" + "</ObjectEvent>";

			EventCapture cap = new EventCapture();
			cap.capture(top + body + bottom);

			Thread.sleep(1000);

			double avg = doTransformationQuery();

			System.out.println(i + "\t" + avg);
			bw.write(i + "\t" + avg + "\n");
			bw.flush();
		}
		bw.close();
	}
 

/**
 * Instantiates a new TagRepository by opening the DB connection.
 */
public TagRepository() {
	mongoClient = new MongoClient("localhost", 27018);
	MongoDatabase database = mongoClient.getDatabase("blog");
	collection = database.getCollection("posts");
}
 

/**
 * Removes an index from a database
 * @param mongo
 * @param dbname
 * @param indexName
 */
public static void dropIndex(MongoClient mongo, String dbname, String indexName) {
	MongoDatabase db = mongo.getDatabase(dbname);
	db.getCollection(indexName + MongoDirectory.BLOCKS_SUFFIX).drop();
	db.getCollection(indexName + MongoDirectory.FILES_SUFFIX).drop();
}