@Override public void filterWrite(NextFilter nextFilter, IoSession session, WriteRequest writeRequest) throws Exception { Object message = writeRequest.getMessage(); // Bypass the encoding if the message is contained in a IoBuffer, // as it has already been encoded before if (message instanceof IoBuffer || message instanceof FileRegion) { nextFilter.filterWrite(session, writeRequest); return; } // Get the encoder in the session ProtocolEncoder encoder = getEncoder(session); ProtocolEncoderOutput encoderOut = getEncoderOut(session, nextFilter, writeRequest); try { // Now we can try to encode the response encoder.encode(session, message, encoderOut); // Send it directly ((ProtocolEncoderOutputImpl) encoderOut).flushWithoutFuture(); // Call the next filter nextFilter.filterWrite(session, new MessageWriteRequest(writeRequest)); } catch (Throwable t) { ProtocolEncoderException pee; // Generate the correct exception if (t instanceof ProtocolEncoderException) { pee = (ProtocolEncoderException) t; } else { pee = new ProtocolEncoderException(t); } throw pee; } }