docs: private static ThreadLocal<MessageDigest> createThreadLocalMessageDigest(final String digest) {
  		return new ThreadLocal<MessageDigest>() {
  			@Override
  			protected MessageDigest initialValue() {
  				try {
  					return MessageDigest.getInstance(digest);
  				} catch (NoSuchAlgorithmException e) {
  					throw new RuntimeException(
  							"unexpected exception creating MessageDigest instance for [" + digest + ']', e);
  				}
  			}
  		};
  	}