code: public static void encodeDesc(Boolean value, byte[] dst, int dstOffset) {
          if (value == null) {
              dst[dstOffset] = NULL_BYTE_LOW;
          } else {
              dst[dstOffset] = value.booleanValue() ? (byte)127 : (byte)128;
          }
      }
docs: Encodes the given Boolean object into exactly 1 byte for descending
  order.
  
  @param value optional Boolean value to encode
  @param dst destination for encoded bytes
  @param dstOffset offset into destination array