private void intToByte(int num) {
      for (int i = 3; i >= 0; i--) {
        seqNum[i] = (byte) (num & 0xff);
        num >>>= 8;
      }
    }
Helper class for providing integrity protection.
hbase-common/src/main/java/org/apache/hadoop/hbase/io/crypto/aes/CryptoAES.java