code: public static byte[] toBytes(long value) {
          byte[] bytes = new byte[8];
          ByteBuffer buffer = ByteBuffer.wrap(bytes);
          buffer.putLong(value);
          return bytes;
      }
docs: Convert a long to a byte[] using the format Cassandra wants for a column or
  supercolumn name. The antimethod for this one is {@link #toLong(byte[])}.
  
  @param value Long value to be converted.
  @return      Same value encoded into an byte[8] array.