All Downloads are FREE. Search and download functionalities are using the official Maven repository.

io.netty.channel.local.LocalChannel Maven / Gradle / Ivy

Go to download

This artifact provides a single jar that contains all classes required to use remote EJB and JMS, including all dependencies. It is intended for use by those not using maven, maven users should just import the EJB and JMS BOM's instead (shaded JAR's cause lots of problems with maven, as it is very easy to inadvertently end up with different versions on classes on the class path).

There is a newer version: 33.0.2.Final
Show newest version
/*
 * Copyright 2012 The Netty Project
 *
 * The Netty Project licenses this file to you under the Apache License,
 * version 2.0 (the "License"); you may not use this file except in compliance
 * with the License. You may obtain a copy of the License at:
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 * License for the specific language governing permissions and limitations
 * under the License.
 */
package io.netty.channel.local;

import io.netty.channel.AbstractChannel;
import io.netty.channel.Channel;
import io.netty.channel.ChannelConfig;
import io.netty.channel.ChannelException;
import io.netty.channel.ChannelMetadata;
import io.netty.channel.ChannelOutboundBuffer;
import io.netty.channel.ChannelPipeline;
import io.netty.channel.ChannelPromise;
import io.netty.channel.DefaultChannelConfig;
import io.netty.channel.EventLoop;
import io.netty.channel.SingleThreadEventLoop;
import io.netty.util.ReferenceCountUtil;
import io.netty.util.concurrent.SingleThreadEventExecutor;
import io.netty.util.internal.InternalThreadLocalMap;

import java.net.SocketAddress;
import java.nio.channels.AlreadyConnectedException;
import java.nio.channels.ClosedChannelException;
import java.nio.channels.ConnectionPendingException;
import java.nio.channels.NotYetConnectedException;
import java.util.ArrayDeque;
import java.util.Collections;
import java.util.Queue;

/**
 * A {@link Channel} for the local transport.
 */
public class LocalChannel extends AbstractChannel {

    private static final ChannelMetadata METADATA = new ChannelMetadata(false);

    private static final int MAX_READER_STACK_DEPTH = 8;

    private final ChannelConfig config = new DefaultChannelConfig(this);
    private final Queue inboundBuffer = new ArrayDeque();
    private final Runnable readTask = new Runnable() {
        @Override
        public void run() {
            ChannelPipeline pipeline = pipeline();
            for (;;) {
                Object m = inboundBuffer.poll();
                if (m == null) {
                    break;
                }
                pipeline.fireChannelRead(m);
            }
            pipeline.fireChannelReadComplete();
        }
    };

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

    private volatile int state; // 0 - open, 1 - bound, 2 - connected, 3 - closed
    private volatile LocalChannel peer;
    private volatile LocalAddress localAddress;
    private volatile LocalAddress remoteAddress;
    private volatile ChannelPromise connectPromise;
    private volatile boolean readInProgress;
    private volatile boolean registerInProgress;

    public LocalChannel() {
        super(null);
    }

    LocalChannel(LocalServerChannel parent, LocalChannel peer) {
        super(parent);
        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();
    }

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

    @Override
    public boolean isOpen() {
        return state < 3;
    }

    @Override
    public boolean isActive() {
        return state == 2;
    }

    @Override
    protected AbstractUnsafe newUnsafe() {
        return new LocalUnsafe();
    }

    @Override
    protected boolean isCompatible(EventLoop loop) {
        return loop instanceof SingleThreadEventLoop;
    }

    @Override
    protected SocketAddress localAddress0() {
        return localAddress;
    }

    @Override
    protected SocketAddress remoteAddress0() {
        return remoteAddress;
    }

    @Override
    protected void doRegister() throws Exception {
        // Check if both peer and parent are non-null because this channel was created by a LocalServerChannel.
        // This is needed as a peer may not be null also if a LocalChannel was connected before and
        // deregistered / registered later again.
        //
        // See https://github.com/netty/netty/issues/2400
        if (peer != null && parent() != null) {
            // Store the peer in a local variable as it may be set to null if doClose() is called.
            // Because of this we also set registerInProgress to true as we check for this in doClose() and make sure
            // we delay the fireChannelInactive() to be fired after the fireChannelActive() and so keep the correct
            // order of events.
            //
            // See https://github.com/netty/netty/issues/2144
            final LocalChannel peer = this.peer;
            registerInProgress = true;
            state = 2;

            peer.remoteAddress = parent().localAddress();
            peer.state = 2;

            // 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 channelActive
            // event is triggered *after* this channel's channelRegistered event, so that this channel's
            // pipeline is fully initialized by ChannelInitializer before any channelRead events.
            peer.eventLoop().execute(new Runnable() {
                @Override
                public void run() {
                    registerInProgress = false;
                    peer.pipeline().fireChannelActive();
                    peer.connectPromise.setSuccess();
                }
            });
        }
        ((SingleThreadEventExecutor) eventLoop()).addShutdownHook(shutdownHook);
    }

    @Override
    protected void doBind(SocketAddress localAddress) throws Exception {
        this.localAddress =
                LocalChannelRegistry.register(this, this.localAddress,
                        localAddress);
        state = 1;
    }

    @Override
    protected void doDisconnect() throws Exception {
        doClose();
    }

    @Override
    protected void doClose() throws Exception {
        if (state <= 2) {
            // Update all internal state before the closeFuture is notified.
            if (localAddress != null) {
                if (parent() == null) {
                    LocalChannelRegistry.unregister(localAddress);
                }
                localAddress = null;
            }
            state = 3;
        }

        final LocalChannel peer = this.peer;
        if (peer != null && peer.isActive()) {
            // Need to execute the close in the correct EventLoop
            // See https://github.com/netty/netty/issues/1777
            EventLoop eventLoop = peer.eventLoop();

            // Also check if the registration was not done yet. In this case we submit the close to the EventLoop
            // to make sure it is run after the registration completes.
            //
            // See https://github.com/netty/netty/issues/2144
            if (eventLoop.inEventLoop() && !registerInProgress) {
                peer.unsafe().close(unsafe().voidPromise());
            } else {
                peer.eventLoop().execute(new Runnable() {
                    @Override
                    public void run() {
                        peer.unsafe().close(unsafe().voidPromise());
                    }
                });
            }
            this.peer = null;
        }
    }

    @Override
    protected void doDeregister() throws Exception {
        // Just remove the shutdownHook as this Channel may be closed later or registered to another EventLoop
        ((SingleThreadEventExecutor) eventLoop()).removeShutdownHook(shutdownHook);
    }

    @Override
    protected void doBeginRead() throws Exception {
        if (readInProgress) {
            return;
        }

        ChannelPipeline pipeline = pipeline();
        Queue inboundBuffer = this.inboundBuffer;
        if (inboundBuffer.isEmpty()) {
            readInProgress = true;
            return;
        }

        final InternalThreadLocalMap threadLocals = InternalThreadLocalMap.get();
        final Integer stackDepth = threadLocals.localChannelReaderStackDepth();
        if (stackDepth < MAX_READER_STACK_DEPTH) {
            threadLocals.setLocalChannelReaderStackDepth(stackDepth + 1);
            try {
                for (;;) {
                    Object received = inboundBuffer.poll();
                    if (received == null) {
                        break;
                    }
                    pipeline.fireChannelRead(received);
                }
                pipeline.fireChannelReadComplete();
            } finally {
                threadLocals.setLocalChannelReaderStackDepth(stackDepth);
            }
        } else {
            eventLoop().execute(readTask);
        }
    }

    @Override
    protected void doWrite(ChannelOutboundBuffer in) throws Exception {
        if (state < 2) {
            throw new NotYetConnectedException();
        }
        if (state > 2) {
            throw new ClosedChannelException();
        }

        final LocalChannel peer = this.peer;
        final ChannelPipeline peerPipeline = peer.pipeline();
        final EventLoop peerLoop = peer.eventLoop();

        if (peerLoop == eventLoop()) {
            for (;;) {
                Object msg = in.current();
                if (msg == null) {
                    break;
                }
                peer.inboundBuffer.add(msg);
                ReferenceCountUtil.retain(msg);
                in.remove();
            }
            finishPeerRead(peer, peerPipeline);
        } else {
            // Use a copy because the original msgs will be recycled by AbstractChannel.
            final Object[] msgsCopy = new Object[in.size()];
            for (int i = 0; i < msgsCopy.length; i ++) {
                msgsCopy[i] = ReferenceCountUtil.retain(in.current());
                in.remove();
            }

            peerLoop.execute(new Runnable() {
                @Override
                public void run() {
                    Collections.addAll(peer.inboundBuffer, msgsCopy);
                    finishPeerRead(peer, peerPipeline);
                }
            });
        }
    }

    private static void finishPeerRead(LocalChannel peer, ChannelPipeline peerPipeline) {
        if (peer.readInProgress) {
            peer.readInProgress = false;
            for (;;) {
                Object received = peer.inboundBuffer.poll();
                if (received == null) {
                    break;
                }
                peerPipeline.fireChannelRead(received);
            }
            peerPipeline.fireChannelReadComplete();
        }
    }

    private class LocalUnsafe extends AbstractUnsafe {

        @Override
        public void connect(final SocketAddress remoteAddress,
                SocketAddress localAddress, final ChannelPromise promise) {
            if (!promise.setUncancellable() || !ensureOpen(promise)) {
                return;
            }

            if (state == 2) {
                Exception cause = new AlreadyConnectedException();
                safeSetFailure(promise, cause);
                pipeline().fireExceptionCaught(cause);
                return;
            }

            if (connectPromise != null) {
                throw new ConnectionPendingException();
            }

            connectPromise = promise;

            if (state != 1) {
                // Not bound yet and no localAddress specified - get one.
                if (localAddress == null) {
                    localAddress = new LocalAddress(LocalChannel.this);
                }
            }

            if (localAddress != null) {
                try {
                    doBind(localAddress);
                } catch (Throwable t) {
                    safeSetFailure(promise, t);
                    close(voidPromise());
                    return;
                }
            }

            Channel boundChannel = LocalChannelRegistry.get(remoteAddress);
            if (!(boundChannel instanceof LocalServerChannel)) {
                Exception cause = new ChannelException("connection refused");
                safeSetFailure(promise, cause);
                close(voidPromise());
                return;
            }

            LocalServerChannel serverChannel = (LocalServerChannel) boundChannel;
            peer = serverChannel.serve(LocalChannel.this);
        }
    }
}
 















© 2015 - 2024 Weber Informatics LLC | Privacy Policy