Hash 32 String : MD5 Message Digest algorithm  « Security « Java Tutorial






/*
    GNU LESSER GENERAL PUBLIC LICENSE
    Copyright (C) 2006 The Lobo Project

    This library 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 2.1 of the License, or (at your option) any later version.

    This library 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 this library; if not, write to the Free Software
    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

    Contact info: lobochief@users.sourceforge.net
*/

import java.io.UnsupportedEncodingException;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.util.ArrayList;

public class Strings
{
  private static final MessageDigest MESSAGE_DIGEST;
  public static final String[] EMPTY_ARRAY = new String[0];

  static {
      MessageDigest md;
      try {
          md = MessageDigest.getInstance("MD5");
      } catch(NoSuchAlgorithmException err) {
        throw new IllegalStateException();
      }
      MESSAGE_DIGEST = md;
  }
  private static final String HEX_CHARS = "0123456789ABCDEF";
  
  public static String getMD5(String source) {    
      byte[] bytes;
      try {
        bytes = source.getBytes("UTF-8");
      } catch(java.io.UnsupportedEncodingException ue) {
        throw new IllegalStateException(ue);
      }
      byte[] result;
      synchronized(MESSAGE_DIGEST) {
          MESSAGE_DIGEST.update(bytes);
          result = MESSAGE_DIGEST.digest();
      }
      char[] resChars = new char[32];
      int len = result.length;
      for(int i = 0; i < len; i++) {
          byte b = result[i];
          int lo4 = b & 0x0F;
          int hi4 = (b & 0xF0) >> 4;
          resChars[i*2] = HEX_CHARS.charAt(hi4);
          resChars[i*2 + 1] = HEX_CHARS.charAt(lo4);
      }
      return new String(resChars);
  }
  
  public static String getHash32(String source) throws UnsupportedEncodingException {
      String md5 = getMD5(source);
      return md5.substring(0, 8);
  }      

  public static String getHash64(String source) throws UnsupportedEncodingException {
      String md5 = getMD5(source);
      return md5.substring(0, 16);
  }   
  
}








36.26.MD5 Message Digest algorithm
36.26.1.creates an MD5 message digest from a file and displays it to the screen BASE64 Encoded.
36.26.2.Password Storage Example
36.26.3.Password Authenticator
36.26.4.Check password salt based on MD5
36.26.5.MD5 your password
36.26.6.Set password salt
36.26.7.Check password based on MD5
36.26.8.MD5 MessageDigest your message
36.26.9.Creating a Keyed Digest Using MD5
36.26.10.MD5 String
36.26.11.MD5 hashing: Encodes a string
36.26.12.Get MD5 Base64
36.26.13.MD5 BASE64 checksum for the specified input string.
36.26.14.Encode an MD5 digest into a String.
36.26.15.Hash 32 String
36.26.16.Hash 64 String