LocalChannel Class — netty Architecture

Source Code

transport/src/main/java/io/netty/channel/local/LocalChannel.java lines 54–586

public class LocalChannel extends AbstractChannel {
    private static final InternalLogger logger = InternalLoggerFactory.getInstance(LocalChannel.class);
    @SuppressWarnings({ "rawtypes" })
    private static final AtomicReferenceFieldUpdater<LocalChannel, Future> FINISH_READ_FUTURE_UPDATER =
            AtomicReferenceFieldUpdater.newUpdater(LocalChannel.class, Future.class, "finishReadFuture");
    private static final ChannelMetadata METADATA = new ChannelMetadata(false);
    private static final int MAX_READER_STACK_DEPTH = 8;

    private enum State { OPEN, BOUND, CONNECTED, CLOSED }

    private final ChannelConfig config = new DefaultChannelConfig(this);
    // To further optimize this we could write our own SPSC queue.
    final Queue<Object> inboundBuffer = PlatformDependent.newSpscQueue();
    private final Runnable readTask = new Runnable() {
        @Override
        public void run() {
            // Ensure the inboundBuffer is not empty as readInbound() will always call fireChannelReadComplete()
            if (!inboundBuffer.isEmpty()) {
                readInbound();
            }
        }
    };

    private final Runnable shutdownHook = new Runnable() {
        @Override
        public void run() {
            unsafe().close(unsafe().voidPromise());
        }
    };

    private final Runnable finishReadTask = new Runnable() {
        @Override
        public void run() {
            finishPeerRead0(LocalChannel.this);
        }
    };

    private IoRegistration registration;

    private volatile State state;
    private volatile LocalChannel peer;
    private volatile LocalAddress localAddress;
    private volatile LocalAddress remoteAddress;
    private volatile ChannelPromise connectPromise;
    private volatile boolean readInProgress;
    private volatile boolean writeInProgress;
    private volatile Future<?> finishReadFuture;

    public LocalChannel() {
        super(null);
        config().setAllocator(new PreferHeapByteBufAllocator(config.getAllocator()));
    }

    protected LocalChannel(LocalServerChannel parent, LocalChannel peer) {
        super(parent);
        config().setAllocator(new PreferHeapByteBufAllocator(config.getAllocator()));
        this.peer = peer;
        localAddress = parent.localAddress();
        remoteAddress = peer.localAddress();
    }

    @Override
    public ChannelMetadata metadata() {
        return METADATA;
    }

    @Override
    public ChannelConfig config() {
        return config;
    }

    @Override
    public LocalServerChannel parent() {
        return (LocalServerChannel) super.parent();
    }

    @Override
    public LocalAddress localAddress() {
        return (LocalAddress) super.localAddress();
    }