public NextAction handleRead()

in dubbo-remoting-extensions/dubbo-remoting-grizzly/src/main/java/org/apache/dubbo/remoting/transport/grizzly/GrizzlyCodecAdapter.java [86:141]
52 lines of code
10 McCabe index (conditional complexity)

    public NextAction handleRead(FilterChainContext context) throws IOException {
        Object message = context.getMessage();
        Connection<?> connection = context.getConnection();
        Channel channel = GrizzlyChannel.getOrAddChannel(connection, url, handler);
        try {
            if (message instanceof Buffer) { // receive a new packet
                Buffer grizzlyBuffer = (Buffer) message; // buffer

                ChannelBuffer frame;

                if (previousData.readable()) {
                    if (previousData instanceof DynamicChannelBuffer) {
                        previousData.writeBytes(grizzlyBuffer.toByteBuffer());
                        frame = previousData;
                    } else {
                        int size = previousData.readableBytes() + grizzlyBuffer.remaining();
                        frame = ChannelBuffers.dynamicBuffer(size > bufferSize ? size : bufferSize);
                        frame.writeBytes(previousData, previousData.readableBytes());
                        frame.writeBytes(grizzlyBuffer.toByteBuffer());
                    }
                } else {
                    frame = ChannelBuffers.wrappedBuffer(grizzlyBuffer.toByteBuffer());
                }

                Object msg;
                int savedReadIndex;

                do {
                    savedReadIndex = frame.readerIndex();
                    try {
                        msg = codec.decode(channel, frame);
                    } catch (Exception e) {
                        previousData = ChannelBuffers.EMPTY_BUFFER;
                        throw new IOException(e.getMessage(), e);
                    }
                    if (msg == Codec2.DecodeResult.NEED_MORE_INPUT) {
                        frame.readerIndex(savedReadIndex);
                        return context.getStopAction();
                    } else {
                        if (savedReadIndex == frame.readerIndex()) {
                            previousData = ChannelBuffers.EMPTY_BUFFER;
                            throw new IOException("Decode without read data.");
                        }
                        if (msg != null) {
                            context.setMessage(msg);
                        }
                        return context.getInvokeAction();
                    }
                } while (frame.readable());
            } else { // Other events are passed down directly
                return context.getInvokeAction();
            }
        } finally {
            GrizzlyChannel.removeChannelIfDisconnected(connection);
        }
    }