code: private void readBody() {
          final ByteBuf buf = readBytes(requiredLength);
          final ByteBufOrStream msg = compressedFlag ? getCompressedBody(buf) : getUncompressedBody(buf);
          listener.messageRead(msg);
  
          // Done with this frame, begin processing the next header.
          state = State.HEADER;
          requiredLength = HEADER_LENGTH;
      }
docs: Processes the body of the gRPC compression frame. A single compression frame may contain
  several gRPC messages within it.