class AMQ::Protocol::HeaderFrame

def decode_payload
  @decoded_payload ||= begin
                         @klass_id, @weight = @payload.unpack(PACK_UINT16_X2)
                         # the total size of the content body, that is, the sum of the body sizes for the
                         # following content body frames. Zero indicates that there are no content body frames.
                         # So this is NOT related to this very header frame!
                         @body_size         = AMQ::Hacks.unpack_uint64_big_endian(@payload[4..11]).first
                         @data              = @payload[12..-1]
                         @properties        = Basic.decode_properties(@data)
                       end
end