MessageDigestUtils.java

/*
 * XAdES4j - A Java library for generation and verification of XAdES signatures.
 * Copyright (C) 2011 Luis Goncalves.
 * 
 * XAdES4j is free software; you can redistribute it and/or modify it under
 * the terms of the GNU Lesser General Public License as published by the Free
 * Software Foundation; either version 3 of the License, or any later version.
 * 
 * XAdES4j 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.
 * 
 * You should have received a copy of the GNU Lesser General Public License along
 * with XAdES4j. If not, see <http://www.gnu.org/licenses/>.
 */
package xades4j.utils;

import java.io.IOException;
import java.io.InputStream;
import java.security.MessageDigest;

/**
 *
 * @author Luís
 */
public class MessageDigestUtils
{
    private MessageDigestUtils()
    {
    }

    public static byte[] digestStream(MessageDigest digest, InputStream is) throws IOException
    {
        byte[] buf = new byte[4096];
        int nRead;
        while ((nRead = is.read(buf)) != -1)
        {
            digest.update(buf, 0, nRead);
        }
        
        return digest.digest();
    }
}