Ruby implementation:

require 'digest/md5'
digest = Digest::MD5.hexdigest("encrypt this text")

PHP implementation:

<?php
   $str = "Hello";
   echo md5($str);
?>

Java implementation (2 methods for clarity):

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

public class MD5 {

public static String digest(String text) {
      throws NoSuchAlgorithmException, UnsupportedEncodingException {
   MessageDigest md = MessageDigest.getInstance("MD5");
   byte[] md5hash = new byte[32];
   md.update(text.getBytes("iso-8859-1"), 0, text.length());
   md5hash = md.digest();
   return convertToHex(md5hash);
}

private static String convertToHex(byte[] b) {
   StringBuilder result = new StringBuilder(32);
   for (int i = 0; i < b.length; i++) {
      result.append(
         Integer.toString( ( b[i] & 0xff ) + 0x100, 16).substring( 1 ));
   }
   return result.toString();
}
}

This isn’t the fastest MD5 implementation, but that isn’t my goal here. I found quite a few implementations when searching, some of which gave results which were not even correct!

Hope this implementation helps someone else.

gem install activerecord

Then, the code below is all you need to get started (with an example DAO – DvdTitle at the end)

require "rubygems"
require 'active_record'

ActiveRecord::Base.establish_connection(
  :adapter => "mysql",
  :host => "127.0.0.1",
  :username => "username",
  :database => "dvdsale_development",
  :password => "secret")

class DvdTitle < ActiveRecord::Base
end

puts DvdTitle.find(1).name

My environment:

Ruby version 1.8.6 (i386-mswin32)
RubyGems version 1.3.3
Rails version 2.2.2
Active Record version 2.2.2