code: public static int getOffsetFromQualifier(final byte[] qualifier, 
        final int offset) {
      validateQualifier(qualifier, offset);
      if ((qualifier[offset] & Const.MS_BYTE_FLAG) == Const.MS_BYTE_FLAG) {
        return (int)(Bytes.getUnsignedInt(qualifier, offset) & 0x0FFFFFC0) 
          >>> Const.MS_FLAG_BITS;
      } else {
        final int seconds = (Bytes.getUnsignedShort(qualifier, offset) & 0xFFFF) 
          >>> Const.FLAG_BITS;
        return seconds * 1000;
      }
    }
docs: Returns the offset in milliseconds from the row base timestamp from a data
  point qualifier at the given offset (for compacted columns)
  @param qualifier The qualifier to parse
  @param offset An offset within the byte array
  @return The offset in milliseconds from the base time
  @throws IllegalDataException if the qualifier is null or the offset falls
  outside of the qualifier array
  @since 2.0