doClose() — netty Function Reference

Source Code

transport/src/main/java/io/netty/channel/local/LocalChannel.java lines 221–289

    @Override
    protected void doClose() throws Exception {
        final LocalChannel peer = this.peer;
        State oldState = state;
        try {
            if (oldState != State.CLOSED) {
                // Update all internal state before the closeFuture is notified.
                if (localAddress != null) {
                    if (parent() == null) {
                        LocalChannelRegistry.unregister(localAddress);
                    }
                    localAddress = null;
                }

                // State change must happen before finishPeerRead to ensure writes are released either in doWrite or
                // channelRead.
                state = State.CLOSED;

                // Preserve order of event and force a read operation now before the close operation is processed.
                if (writeInProgress && peer != null) {
                    finishPeerRead(peer);
                }

                ChannelPromise promise = connectPromise;
                if (promise != null) {
                    // Use tryFailure() instead of setFailure() to avoid the race against cancel().
                    promise.tryFailure(new ClosedChannelException());
                    connectPromise = null;
                }
            }

            if (peer != null) {
                this.peer = null;
                // Always call peer.eventLoop().execute() even if peer.eventLoop().inEventLoop() is true.
                // This ensures that if both channels are on the same event loop, the peer's channelInActive
                // event is triggered *after* this peer's channelInActive event
                EventLoop peerEventLoop = peer.eventLoop();
                final boolean peerIsActive = peer.isActive();
                try {
                    peerEventLoop.execute(new Runnable() {
                        @Override
                        public void run() {
                            peer.tryClose(peerIsActive);
                        }
                    });
                } catch (Throwable cause) {
                    logger.warn("Releasing Inbound Queues for channels {}-{} because exception occurred!",
                            this, peer, cause);
                    if (peerEventLoop.inEventLoop()) {
                        peer.releaseInboundBuffers();
                    } else {
                        // inboundBuffers is a SPSC so we may leak if the event loop is shutdown prematurely or
                        // rejects the close Runnable but give a best effort.
                        peer.close();
                    }
                    PlatformDependent.throwException(cause);
                }
            }
        } finally {
            // Release all buffers if the Channel was already registered in the past and if it was not closed before.
            if (oldState != null && oldState != State.CLOSED) {
                // We need to release all the buffers that may be put into our inbound queue since we closed the Channel
                // to ensure we not leak any memory. This is fine as it basically gives the same guarantees as TCP which
                // means even if the promise was notified before its not really guaranteed that the "remote peer" will
                // see the buffer at all.
                releaseInboundBuffers();
            }
        }
    }