Md5ChecksummerImpl.java

/*******************************************************************************
 * $Id: $
 * Copyright (c) 2009-2010 Tim Tiemens.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the GNU Lesser Public License v2.1
 * which accompanies this distribution, and is available at
 * http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Lesser General Public License for more details.
 *
 *
 * Contributors:
 *     Tim Tiemens - initial API and implementation
 ******************************************************************************/
package com.aegiswallet.helpers.secretshare.hashchecks;

import com.aegiswallet.helpers.secretshare.SecretShareException;

import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;


public class Md5ChecksummerImpl
        implements
        Md5Checksummer {


    // ==================================================
    // class static data
    // ==================================================

    // ==================================================
    // class static methods
    // ==================================================

    // ==================================================
    // instance data
    // ==================================================
    private final MessageDigest digest;

    // ==================================================
    // factories
    // ==================================================

    // ==================================================
    // constructors
    // ==================================================

    /**
     * @throws SecretShareException if something goes wrong on construction
     */
    public Md5ChecksummerImpl() {
        try {
            digest = MessageDigest.getInstance("MD5");
        } catch (NoSuchAlgorithmException e) {
            throw new SecretShareException("failed to create md5 digest", e);
        }
    }

    // ==================================================
    // public methods
    // ==================================================
    @Override
    public synchronized byte[] createMd5Checksum(final byte[] in) {
        digest.reset();

        digest.update(in);

        byte[] bytes = digest.digest();

        return bytes;
    }

    // ==================================================
    // non public methods
    // ==================================================
}