com.geeksanon.UserDAO.java Source code

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Here is the source code for com.geeksanon.UserDAO.java

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/**
 * Copyright (c) 2013 Swathi Venkatachala
 * 
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the
 * "Software"), to deal in the Software without restriction, including
 * without limitation the rights to use, copy, modify, merge, publish,
 * distribute, sublicense, and/or sell copies of the Software, and to permit
 * persons to whom the Software is furnished to do so, subject to the
 * following conditions:
 * 
 * The above copyright notice and this permission notice shall be included
 * in all copies or substantial portions of the Software.
 * 
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
 * NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
 * USE OR OTHER DEALINGS IN THE SOFTWARE.
 * 
 * ---------------------------END COPYRIGHT--------------------------------------
 */
package com.geeksanon;

import java.io.UnsupportedEncodingException;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.security.SecureRandom;
import java.util.Random;

import org.apache.log4j.Logger;

import sun.misc.BASE64Encoder;

import com.mongodb.BasicDBObject;
import com.mongodb.DB;
import com.mongodb.DBCollection;
import com.mongodb.DBObject;
import com.mongodb.MongoException;

/**
 * A Data Access Object class with the collection users, performing all
 * necessary operations or querying on it.
 * 
 * @author Swathi V
 * 
 */
public class UserDAO {

    /** Instance of collection **/
    private final DBCollection userCollection;

    /** Obtain the logger instance for logging **/
    private static final Logger LOGGER = Logger.getLogger(UserDAO.class);

    /**
     * Gets the users collection from the database.
     * 
     * @param database
     *            is the database
     */
    public UserDAO(DB database) {
        userCollection = database.getCollection("users");
    }

    /**
     * @param username
     * @param password
     * @return
     */
    public DBObject validateLoginCred(String username, String password) {
        DBObject user = userCollection.findOne(new BasicDBObject("_id", username));
        if (user == null) {
            LOGGER.error("User: " + username + " not found!");
            return null;
        }
        String hashedPassword = user.get("password").toString();
        String extra = hashedPassword.split(",")[1];
        if (!hashedPassword.equals(createHashPassword(password, extra))) {
            LOGGER.error("Password does not match!");
            return null;
        }
        return user;
    }

    /**
     * @param password
     * @param extra
     * @return
     */
    private String createHashPassword(String password, String extra) {
        try {
            String passwordExtra = password + "," + extra;
            MessageDigest messageDigest = MessageDigest.getInstance("MD5");
            messageDigest.update(passwordExtra.getBytes());
            BASE64Encoder encoder = new BASE64Encoder();
            byte hashedBytes[] = (new String(messageDigest.digest(), "UTF-8")).getBytes();
            return encoder.encode(hashedBytes) + "," + extra;
        } catch (NoSuchAlgorithmException e) {
            throw new RuntimeException("MD5 algorithm is not available", e);
        } catch (UnsupportedEncodingException e) {
            throw new RuntimeException("UTF-8 Format unavailable?", e);
        }
    }

    /**
     * Add the user to the database.
     * 
     * @param username
     *            username
     * @param password
     *            password
     * @param email
     *            email
     * @return boolean if added/ not
     */
    public boolean addUser(String username, String password, String email) {
        String hashedPassword = createHashPassword(password, Integer.toString(new SecureRandom().nextInt()));
        BasicDBObject user = new BasicDBObject().append("_id", username).append("password", hashedPassword);
        if (email != null && !email.equals("")) {
            user.append("email", email);
        }
        try {
            userCollection.insert(user);
            return true;
        } catch (MongoException.DuplicateKey e) {
            LOGGER.error("Username exists!");
            return false;
        }
    }
}