com.silverpeas.util.cryptage.CryptMD5.java Source code

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Here is the source code for com.silverpeas.util.cryptage.CryptMD5.java

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/**
 * Copyright (C) 2000 - 2012 Silverpeas
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as
 * published by the Free Software Foundation, either version 3 of the
 * License, or (at your option) any later version.
 *
 * As a special exception to the terms and conditions of version 3.0 of
 * the GPL, you may redistribute this Program in connection with Free/Libre
 * Open Source Software ("FLOSS") applications as described in Silverpeas's
 * FLOSS exception.  You should have received a copy of the text describing
 * the FLOSS exception, and it is also available here:
 * "http://www.silverpeas.org/docs/core/legal/floss_exception.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 Affero General Public License for more details.
 *
 * You should have received a copy of the GNU Affero General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

package com.silverpeas.util.cryptage;

import com.google.common.io.Closeables;
import com.stratelia.webactiv.util.exception.SilverpeasException;
import com.stratelia.webactiv.util.exception.UtilException;

import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.UnsupportedEncodingException;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;

public class CryptMD5 {

    /*
     * Encode la chaine passe en paramtre avec lalgorithme MD5
     * @param original : la chaine  encoder
     * @return la valeur (string) hexadcimale sur 32 bits
     */
    public static String crypt(String original) throws UtilException {

        byte[] uniqueKey = original.getBytes();

        // on rcupre un objet qui permettra de crypter la chaine
        byte[] hash;
        try {
            hash = MessageDigest.getInstance("MD5").digest(uniqueKey);
        } catch (NoSuchAlgorithmException e) {
            // TODO utiliser le CryptageException
            // throw new CryptageException
            throw new UtilException("CryptMD5.crypt()", SilverpeasException.ERROR, "root.EX_NO_MESSAGE", e);
        }

        StringBuilder hashString = new StringBuilder();
        String hex;
        for (byte aHash : hash) {
            hex = Integer.toHexString(aHash);
            if (hex.length() == 1) {
                hashString.append('0');
                hashString.append(hex.charAt(hex.length() - 1));
            } else {
                hashString.append(hex.substring(hex.length() - 2));
            }
        }
        return hashString.toString();
    }

    /*
     * Compute the MD5 hash of a file.
     * @param file: the file to be MD5 hashed.
     * @return the MD5 hash as a String.
     */
    public static String hash(File file) throws UtilException {
        MessageDigest digest;
        FileInputStream fileInputStream = null;
        try {
            digest = MessageDigest.getInstance("MD5");
            fileInputStream = new FileInputStream(file);
            byte[] buffer = new byte[8];
            int c = 0;
            while ((c = fileInputStream.read(buffer)) != -1) {
                digest.update(buffer, 0, c);
            }
            byte[] signature = digest.digest();
            return getHexString(signature);
        } catch (NoSuchAlgorithmException e) {
            throw new UtilException("CryptMD5.hash()", SilverpeasException.ERROR, "root.EX_NO_MESSAGE", e);
        } catch (IOException e) {
            throw new UtilException("CryptMD5.hash()", SilverpeasException.ERROR, "root.EX_NO_MESSAGE", e);
        } finally {
            if (fileInputStream != null) {
                Closeables.closeQuietly(fileInputStream);
            }
        }
    }

    static final byte[] HEX_CHAR_TABLE = { (byte) '0', (byte) '1', (byte) '2', (byte) '3', (byte) '4', (byte) '5',
            (byte) '6', (byte) '7', (byte) '8', (byte) '9', (byte) 'a', (byte) 'b', (byte) 'c', (byte) 'd',
            (byte) 'e', (byte) 'f' };

    protected static String getHexString(byte[] rawData) throws UnsupportedEncodingException {
        byte[] hex = new byte[2 * rawData.length];
        int index = 0;
        for (byte raw : rawData) {
            int v = raw & 0xFF;
            hex[index++] = HEX_CHAR_TABLE[v >>> 4];
            hex[index++] = HEX_CHAR_TABLE[v & 0xF];
        }
        return new String(hex, "ASCII");
    }
}