ch.bfh.uniboard.persistence.mongodb.ConnectionManagerImpl.java Source code

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Here is the source code for ch.bfh.uniboard.persistence.mongodb.ConnectionManagerImpl.java

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/*
 * Copyright (c) 2014 Berner Fachhochschule, Switzerland.
 * Bern University of Applied Sciences, Engineering and Information Technology,
 * Research Institute for Security in the Information Society, E-Voting Group,
 * Biel, Switzerland.
 *
 * Project UniBoard.
 *
 * Distributable under GPL license.
 * See terms of license at gnu.org.
 */
package ch.bfh.uniboard.persistence.mongodb;

import ch.bfh.uniboard.service.ConfigurationManager;
import com.mongodb.DB;
import com.mongodb.DBCollection;
import com.mongodb.MongoClient;
import com.mongodb.MongoCredential;
import com.mongodb.ServerAddress;
import java.net.UnknownHostException;
import java.util.Arrays;
import java.util.Properties;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.annotation.PostConstruct;
import javax.annotation.PreDestroy;
import javax.ejb.EJB;
import javax.ejb.LocalBean;
import javax.ejb.Singleton;
import javax.ejb.Startup;

/**
 *
 * @author Severin Hauser <severin.hauser@bfh.ch>
 */
@Singleton
@Startup
@LocalBean
public class ConnectionManagerImpl implements ConnectionManager {

    private static final Logger logger = Logger.getLogger(ConnectionManagerImpl.class.getName());

    private static final String CONFIG_NAME = "bfh-mongodb";
    private static final String HOST_KEY = "host";
    private static final String DBNAME_KEY = "dbname";
    private static final String COLLECTION_KEY = "collection";
    private static final String PORT_KEY = "port";
    private static final String USERNAME_KEY = "username";
    private static final String PASSWORD_KEY = "password";
    private static final String AUTH_KEY = "authentication";

    private DBCollection collection;
    private MongoClient mongoClient;
    private boolean connected = false;

    @EJB
    ConfigurationManager cm;

    @PostConstruct
    private void init() {

        Properties props = cm.getConfiguration(CONFIG_NAME);

        if (props == null) {
            logger.log(Level.SEVERE, "Configuration could not be loaded.");
            return;
        }
        //DB Connection Information
        String host;
        String dbName;
        String collectionName;
        int port;
        String username;
        String password;
        boolean authentication;
        //Check if values are set or use defaults
        if (props.containsKey(HOST_KEY)) {
            host = props.getProperty(HOST_KEY);
        } else {
            host = "localhost";
        }
        if (props.containsKey(DBNAME_KEY)) {
            dbName = props.getProperty(DBNAME_KEY);
        } else {
            dbName = "uniboard";
        }
        if (props.containsKey(COLLECTION_KEY)) {
            collectionName = props.getProperty(COLLECTION_KEY);
        } else {
            collectionName = "default";
        }
        if (props.containsKey(PORT_KEY)) {
            port = Integer.parseInt(props.getProperty(PORT_KEY));
        } else {
            port = 27017;
        }
        if (props.containsKey(USERNAME_KEY)) {
            username = props.getProperty(USERNAME_KEY);
        } else {
            username = "admin";
        }
        if (props.containsKey(PASSWORD_KEY)) {
            password = props.getProperty(PASSWORD_KEY);
        } else {
            password = "password";
        }
        if (props.containsKey(AUTH_KEY)) {
            authentication = Boolean.parseBoolean(props.getProperty(AUTH_KEY));
        } else {
            authentication = false;
        }

        try {
            if (authentication) {
                MongoCredential credential = MongoCredential.createMongoCRCredential(username, dbName,
                        password.toCharArray());
                //MongoClient already works as a pool if only one instance is used (http://docs.mongodb.org/ecosystem/tutorial/getting-started-with-java-driver/)
                mongoClient = new MongoClient(new ServerAddress(host, port), Arrays.asList(credential));
            } else {
                mongoClient = new MongoClient(host, port);
            }
            this.connected = true;
        } catch (UnknownHostException ex) {
            logger.log(Level.SEVERE, "DB creation error", ex);
            return;
        }

        //Create or load the database
        DB db = mongoClient.getDB(dbName);

        //create the collection if it does not exist
        if (!db.collectionExists(collectionName)) {
            collection = db.createCollection(collectionName, null);
        }
        //load the collection
        collection = db.getCollection(collectionName);
    }

    @PreDestroy
    private void preDestroy() {
        mongoClient.close();
    }

    @Override
    public DBCollection getCollection() {
        return this.collection;
    }

    @Override
    public boolean isConnected() {
        return connected;
    }

}