docs: @Override
      public int size () {
          int size = Smb2Constants.SMB2_HEADER_LENGTH + 36 + size8(2 * this.dialects.length, 4);
          if ( this.negotiateContexts != null ) {
              for ( NegotiateContextRequest ncr : this.negotiateContexts ) {
                  size += 8 + size8(ncr.size());
              }
          }
          return size8(size);
      }