public void parse()

in protonj2/src/main/java/org/apache/qpid/protonj2/engine/impl/ProtonFrameDecodingHandler.java [341:397]
41 lines of code
7 McCabe index (conditional complexity)

        public void parse(EngineHandlerContext context, ProtonBuffer input) {
            int dataOffset = (input.readByte() << 2) & 0x3FF;
            int frameSize = length + FRAME_SIZE_BYTES;

            validateDataOffset(dataOffset, frameSize);

            int type = input.readByte() & 0xFF;
            short channel = input.readShort();

            // Skip over the extended header if present (i.e offset > 8)
            if (dataOffset != 8) {
                input.advanceReadOffset(dataOffset - 8);
            }

            final int frameBodySize = frameSize - dataOffset;

            ProtonBuffer payload = null;
            Object val = null;

            if (frameBodySize > 0) {
                int startReadIndex = input.getReadOffset();
                val = decoder.readObject(input, decoderState);

                // Copy the payload portion of the incoming bytes for now as the incoming may be
                // from a wrapped pooled buffer and for now we have no way of retaining or otherwise
                // ensuring that the buffer remains ours.  Since we might want to store received
                // data at a client level and decode later we could end up losing the data to reuse
                // if it was pooled.
                if (input.isReadable()) {
                    int payloadSize = frameBodySize - (input.getReadOffset() - startReadIndex);
                    if (payloadSize > 0) {
                        // Payload is now only a view of the bytes from the input that comprise it.
                        payload = input.copy(input.getReadOffset(), payloadSize, true);
                        input.advanceReadOffset(payloadSize);
                    }
                }
            } else {
                transitionToFrameSizeParsingStage();
                context.fireRead(EmptyEnvelope.INSTANCE);
                return;
            }

            if (type == AMQP_FRAME_TYPE) {
                Performative performative = (Performative) val;
                IncomingAMQPEnvelope frame = framePool.take(performative, channel, payload);
                transitionToFrameSizeParsingStage();
                context.fireRead(frame);
            } else if (type == SASL_FRAME_TYPE) {
                SaslPerformative performative = (SaslPerformative) val;
                SASLEnvelope saslFrame = new SASLEnvelope(performative);
                transitionToFrameSizeParsingStage();
                // Ensure we process transition from SASL to AMQP header state
                handleRead(context, saslFrame);
            } else {
                throw new FrameDecodingException(String.format("unknown frame type: %d", type));
            }
        }