MD5 in scala

gistfile1.scala

object MD5 {
  def hash(s: String) = {
    val m = java.security.MessageDigest.getInstance("MD5")
    val b = s.getBytes("UTF-8")
    m.update(b, 0, b.length)
    new java.math.BigInteger(1, m.digest()).toString(16)
  }
}

If 0 is the first character, this function will omit it and give an incorrect result.

Yes, @goofyz is right. This does not work for hashes with leading zeros, they are skipped. For example if you caluclate hash("iwrupvqb346386") you'll get 45c5e2b3911eb937d9d8c574f09 instead of 0000045c5e2b3911eb937d9d8c574f09 .

As a remedy, you could do new java.math.BigInteger(1, m.digest()).toString(16).reverse.padTo(32, "0").reverse.mkString in the last line.

On StackOverflow you find code like m.digest().map("%02x".format(_)).mkString which also works but is slower.