MD5 Hash In Java

November 15, 2011

I needed to produce an MD5 hash in Java, in order to integrate with a credit card processing system.

This can be done with the following code:

byte[] lBytesOfMessage = lStringToEncode.toString().getBytes("UTF-8");
MessageDigest lMessageDigest = MessageDigest.getInstance("MD5");
byte[] lDigestBytes = lMessageDigest.digest(lBytesOfMessage);

To return this byte array as a hex string, the following function from commons-codec can be used:

String lReturn = new String(Hex.encodeHex(lDigestBytes));

or even more simply:

String lReturn = Hex.encodeHexString(lDigestBytes);


Tags: codec md5 java hex