public final void onOutput()

in httpcore5-h2/src/main/java/org/apache/hc/core5/http2/impl/nio/AbstractH2StreamMultiplexer.java [452:542]
88 lines of code
32 McCabe index (conditional complexity)

    public final void onOutput() throws HttpException, IOException {
        ioSession.getLock().lock();
        try {
            if (!outputBuffer.isEmpty()) {
                outputBuffer.flush(ioSession);
            }
            while (outputBuffer.isEmpty()) {
                final RawFrame frame = outputQueue.poll();
                if (frame != null) {
                    if (streamListener != null) {
                        streamListener.onFrameOutput(this, frame.getStreamId(), frame);
                    }
                    outputBuffer.write(frame, ioSession);
                } else {
                    break;
                }
            }
        } finally {
            ioSession.getLock().unlock();
        }

        if (connState.compareTo(ConnectionHandshake.SHUTDOWN) < 0) {

            if (connOutputWindow.get() > 0 && remoteSettingState == SettingsHandshake.ACKED) {
                produceOutput();
            }
            final int pendingOutputRequests = outputRequests.get();
            boolean outputPending = false;
            if (!streamMap.isEmpty() && connOutputWindow.get() > 0) {
                for (final Iterator<Map.Entry<Integer, H2Stream>> it = streamMap.entrySet().iterator(); it.hasNext(); ) {
                    final Map.Entry<Integer, H2Stream> entry = it.next();
                    final H2Stream stream = entry.getValue();
                    if (!stream.isLocalClosed()
                            && stream.getOutputWindow().get() > 0
                            && stream.isOutputReady()) {
                        outputPending = true;
                        break;
                    }
                }
            }
            ioSession.getLock().lock();
            try {
                if (!outputPending && outputBuffer.isEmpty() && outputQueue.isEmpty()
                        && outputRequests.compareAndSet(pendingOutputRequests, 0)) {
                    ioSession.clearEvent(SelectionKey.OP_WRITE);
                } else {
                    outputRequests.addAndGet(-pendingOutputRequests);
                }
            } finally {
                ioSession.getLock().unlock();
            }
        }

        if (connState.compareTo(ConnectionHandshake.ACTIVE) <= 0 && remoteSettingState == SettingsHandshake.ACKED) {
            processPendingCommands();
        }
        if (connState.compareTo(ConnectionHandshake.GRACEFUL_SHUTDOWN) == 0) {
            int liveStreams = 0;
            for (final Iterator<Map.Entry<Integer, H2Stream>> it = streamMap.entrySet().iterator(); it.hasNext(); ) {
                final Map.Entry<Integer, H2Stream> entry = it.next();
                final H2Stream stream = entry.getValue();
                if (stream.isLocalClosed() && stream.isRemoteClosed()) {
                    stream.releaseResources();
                    it.remove();
                } else {
                    if (idGenerator.isSameSide(stream.getId()) || stream.getId() <= processedRemoteStreamId) {
                        liveStreams++;
                    }
                }
            }
            if (liveStreams == 0) {
                connState = ConnectionHandshake.SHUTDOWN;
            }
        }
        if (connState.compareTo(ConnectionHandshake.SHUTDOWN) >= 0) {
            if (!streamMap.isEmpty()) {
                for (final H2Stream stream : streamMap.values()) {
                    stream.releaseResources();
                }
                streamMap.clear();
            }
            ioSession.getLock().lock();
            try {
                if (outputBuffer.isEmpty() && outputQueue.isEmpty()) {
                    ioSession.close();
                }
            } finally {
                ioSession.getLock().unlock();
            }
        }
    }