Java Channel類代碼示例

import io.netty.channel.Channel; //導入依賴的package包/類
public void scanNotActiveChannel(){
  	try {
  		 if (this.groupChannelLock.tryLock(LOCK_TIMEOUT_MILLIS, TimeUnit.MILLISECONDS)) {
  			 for(Entry<String,Set<Channel>> entry : groupChannelTable.entrySet()){
  				 if(CollectionUtils.isEmpty(entry.getValue())){
  					 continue;
  				 }
  				 Iterator<Channel> it = entry.getValue().iterator();
  				 while(it.hasNext()){
  					 Channel c = it.next();
  					 if(!c.isActive()){
  						 it.remove();
  					 }
  				 }
  			 }
  		 }else {
  			 log.warn("ProducerManager scanNotActiveChannel lock timeout");
  		 }
} catch (Exception e) {
	log.error("scanNotActiveChannel",e);
}finally{
	this.groupChannelLock.unlock();
}
  }
 

import io.netty.channel.Channel; //導入依賴的package包/類
public NetworkDispatcher connectToLocal(SocketAddress address)
{
	NetworkDispatcher dispatch = new NetworkDispatcher(this, NetworkSide.CLIENT);

	final EventLoopGroup boss = new DefaultEventLoopGroup();
	final Bootstrap b = new Bootstrap()
			.group(boss)
			.handler(new ChannelInitializer<Channel>() {
				@Override
				protected void initChannel(Channel ch) throws Exception
				{
					ch.pipeline().addLast(dispatch);
				}
			})
			.channel(LocalChannel.class);

	//Connect and wait until done
	b.connect(address).syncUninterruptibly();

	return dispatch;
}
 

import io.netty.channel.Channel; //導入依賴的package包/類
public static boolean start(Channel channel, String name, Logger logger) {
    final PacketEncoder oldEncoder = channel.pipeline().get(PacketEncoder.class);
    final PacketDecoder oldDecoder = channel.pipeline().get(PacketDecoder.class);

    channel.eventLoop().execute(() -> {
        if(channel.isOpen()) {
            if(oldEncoder != null) {
                channel.pipeline().replace(oldEncoder, "encoder", new Encoder(logger, name));
            }

            if(oldDecoder != null) {
                channel.pipeline().replace(oldDecoder, "decoder", new Decoder(logger, name));
            }
        }
    });

    return oldEncoder != null || oldDecoder != null;
}
 

import io.netty.channel.Channel; //導入依賴的package包/類
public ReplyMsg writeAndSync(final Channel channel, final AskMsg askMsg, final long timeout) throws Exception {

        if (channel == null) {
            throw new NullPointerException("channel");
        }
        if (askMsg == null) {
            throw new NullPointerException("askMsg");
        }
        if (timeout <= 0) {
            throw new IllegalArgumentException("timeout <= 0");
        }

        String requestId = UUID.randomUUID().toString();
        askMsg.setRequestId(requestId);

        WriteFuture<BaseMsg> future = new SyncWriteFuture(askMsg.getRequestId());
        SyncWriteMap.syncKey.put(askMsg.getRequestId(), future);

        System.out.println("發起請求，請求id：" + requestId + "，請求參數：" + askMsg.getData());

        ReplyMsg response = doWriteAndSync(channel, askMsg, timeout, future);

        SyncWriteMap.syncKey.remove(askMsg.getRequestId());
        return response;
    }
 

import io.netty.channel.Channel; //導入依賴的package包/類
@Override
protected void handleRegisterRequest(RegisterRequestMessage request,
                                     Channel channel) {
    try {
        Scope scope = TProtocolUtil.getScope(request.store.getScope());
        if (request.store.isPersist())
            syncManager.registerPersistentStore(request.store.storeName,
                                                scope);
        else
            syncManager.registerStore(request.store.storeName, scope);
        RegisterResponseMessage m = new RegisterResponseMessage();
        AsyncMessageHeader header = new AsyncMessageHeader();
        header.setTransactionId(request.getHeader().getTransactionId());
        m.setHeader(header);
        SyncMessage bsm =
                new SyncMessage(MessageType.REGISTER_RESPONSE);
        bsm.setRegisterResponse(m);
        channel.writeAndFlush(bsm);
    } catch (Exception e) {
        channel.writeAndFlush(getError(request.getHeader().getTransactionId(), e,
                               MessageType.REGISTER_REQUEST));
    }
}
 

import io.netty.channel.Channel; //導入依賴的package包/類
@Override
public void preCreateConnections(final int count)
throws ConnectException, IllegalArgumentException {
	if(count > 0) {
		for(int i = 0; i < count; i ++) {
			final Channel conn = connectToAnyNode();
			if(conn == null) {
				throw new ConnectException(
					"Failed to pre-create the connections to the target nodes"
				);
			}
			final String nodeAddr = conn.attr(ATTR_KEY_NODE).get();
			if(conn.isActive()) {
				final Queue<Channel> connQueue = availableConns.get(nodeAddr);
				if(connQueue != null) {
					connQueue.add(conn);
				}
			} else {
				conn.close();
			}
		}
		LOG.info("Pre-created " + count + " connections");
	} else {
		throw new IllegalArgumentException("Connection count should be > 0, but got " + count);
	}
}
 

import io.netty.channel.Channel; //導入依賴的package包/類
protected void handshake(HelloMessage request, Channel channel) {
    try {
        switch (getAuthScheme()) {
            case CHALLENGE_RESPONSE:
                handshakeChallengeResponse(request, channel);
                break;
            case NO_AUTH:
                // shouldn't get here
                break;
        }
    } catch (AuthException e) {
        logger.warn("[{}->{}] Failed to authenticate connection: {}",
                    new Object[]{getLocalNodeIdString(), 
                                 getRemoteNodeIdString(), 
                                 e.getMessage()});
        channel.writeAndFlush(getError(request.getHeader().getTransactionId(), 
                               e, MessageType.HELLO));
        channel.close();
    }
}
 

import io.netty.channel.Channel; //導入依賴的package包/類
/**
 * Adds a channel that listens locally
 */
public SocketAddress addLocalEndpoint()
{
    ChannelFuture channelfuture;

    synchronized (this.endpoints)
    {
        channelfuture = ((ServerBootstrap)((ServerBootstrap)(new ServerBootstrap()).channel(LocalServerChannel.class)).childHandler(new ChannelInitializer<Channel>()
        {
            protected void initChannel(Channel p_initChannel_1_) throws Exception
            {
                NetworkManager networkmanager = new NetworkManager(EnumPacketDirection.SERVERBOUND);
                networkmanager.setNetHandler(new NetHandlerHandshakeMemory(NetworkSystem.this.mcServer, networkmanager));
                NetworkSystem.this.networkManagers.add(networkmanager);
                p_initChannel_1_.pipeline().addLast((String)"packet_handler", (ChannelHandler)networkmanager);
            }
        }).group((EventLoopGroup)eventLoops.getValue()).localAddress(LocalAddress.ANY)).bind().syncUninterruptibly();
        this.endpoints.add(channelfuture);
    }

    return channelfuture.channel().localAddress();
}
 

import io.netty.channel.Channel; //導入依賴的package包/類
/**
 * 對準備接入的 Channel 做進一步處理
 *
 * @param channel 準備接入的 Channel
 */
public void accessibleChannel(Channel channel) {
    String id = channel.id().asLongText();
    logger.info("「Channel」" + "新的 Channel 接入 [" + id + "]");
    CHANNEL_MAP.put(id, -1);
    HASHED_WHEEL_TIMER.newTimeout(task -> {
        Integer index = CHANNEL_MAP.get(id);
        if (index == -1) {
            logger.warn("「Channel」" + "新的 Channel 未反饋 ID [" + id + "]");
            channel.disconnect();
        } else if (index > 0 && index <= DeviceSetting.MAX_GROUP_ID) {
            SENDING_MESSAGE_QUEUE.get(index).clear();
            Channel oldChannel = CHANNEL_ARRAY.get(index);
            if (oldChannel != null && oldChannel.isActive()) {
                manualRemoveChannel(CHANNEL_ARRAY.get(index));
                manualRemoveChannel(channel);
                logger.warn("「Channel」" + "新的 Channel 欲覆蓋已激活的 Channel [" + id + "]");
            } else {
                CHANNEL_ARRAY.set(index, channel);
                logger.info("「Channel」" + "新的 Channel「" + index + "」已成功裝配 [" + id + "]");
            }
        } else {
            logger.warn("「Channel」" + "新的 Channel 裝配出錯 [" + id + "]");
        }
    }, CommSetting.ACCESSIBLE_CHANNEL_REPLY_INTERVAL, TimeUnit.SECONDS);
}
 

import io.netty.channel.Channel; //導入依賴的package包/類
private static Pair<EventLoopGroup, Class<? extends Channel>> createEventLoopGroup(
    Configuration conf) {
  // Max amount of threads to use. 0 lets Netty decide based on amount of cores
  int maxThreads = conf.getInt(CLIENT_MAX_THREADS, 0);

  // Config to enable native transport. Does not seem to be stable at time of implementation
  // although it is not extensively tested.
  boolean epollEnabled = conf.getBoolean(USE_NATIVE_TRANSPORT, false);

  // Use the faster native epoll transport mechanism on linux if enabled
  if (epollEnabled && JVM.isLinux() && JVM.isAmd64()) {
    if (LOG.isDebugEnabled()) {
      LOG.debug("Create EpollEventLoopGroup with maxThreads = " + maxThreads);
    }
    return new Pair<EventLoopGroup, Class<? extends Channel>>(new EpollEventLoopGroup(maxThreads,
        Threads.newDaemonThreadFactory("AsyncRpcChannel")), EpollSocketChannel.class);
  } else {
    if (LOG.isDebugEnabled()) {
      LOG.debug("Create NioEventLoopGroup with maxThreads = " + maxThreads);
    }
    return new Pair<EventLoopGroup, Class<? extends Channel>>(new NioEventLoopGroup(maxThreads,
        Threads.newDaemonThreadFactory("AsyncRpcChannel")), NioSocketChannel.class);
  }
}
 

import io.netty.channel.Channel; //導入依賴的package包/類
/**
	 * 適配
	 */
	@Override
	protected ChannelHandler fixHandlerBeforeConnect(final ChannelHandler handler) {
		ChannelHandler result=new ShareableChannelInboundHandler() {
			@Override
			public void channelRegistered(ChannelHandlerContext ctx) throws Exception {
				Channel ch=ctx.channel();
				ch.pipeline().addLast(new HttpClientCodec());
            	ch.pipeline().addLast(new HttpObjectAggregator(64*1024));
            	ch.pipeline().addLast(new WebSocketClientProtocolHandler(WebSocketClientHandshakerFactory.newHandshaker(uri, WebSocketVersion.V13, null, false, new DefaultHttpHeaders())));
            	ch.pipeline().addLast(new WebSocketConnectedClientHandler(handler));
				ctx.pipeline().remove(this);//移除當前handler
				ctx.pipeline().fireChannelRegistered();//重新從第一個handler拋出事件
			}
		};
//		ChannelInitializer<SocketChannel> result=new ChannelInitializer<SocketChannel>() {
//            @Override
//            protected void initChannel(SocketChannel ch) {
//            	ch.pipeline().addLast(new HttpClientCodec());
//            	ch.pipeline().addLast(new HttpObjectAggregator(64*1024));
//            	ch.pipeline().addLast(new WebSocketClientProtocolHandler(WebSocketClientHandshakerFactory.newHandshaker(uri, WebSocketVersion.V13, null, false, new DefaultHttpHeaders())));
//            	ch.pipeline().addLast(new WebSocketConnectedClientHandler(handler));
//            }
//        };
        return result;
	}
 

import io.netty.channel.Channel; //導入依賴的package包/類
/**
 * Broker主動通知Consumer，Id列表發生變化，Oneway
 */
public void notifyConsumerIdsChanged(
    final Channel channel,
    final String consumerGroup) {
    if (null == consumerGroup) {
        log.error("notifyConsumerIdsChanged consumerGroup is null");
        return;
    }

    NotifyConsumerIdsChangedRequestHeader requestHeader = new NotifyConsumerIdsChangedRequestHeader();
    requestHeader.setConsumerGroup(consumerGroup);
    RemotingCommand request =
        RemotingCommand.createRequestCommand(RequestCode.NOTIFY_CONSUMER_IDS_CHANGED, requestHeader);

    try {
        this.brokerController.getRemotingServer().invokeOneway(channel, request, 10);
    } catch (Exception e) {
        log.error("notifyConsumerIdsChanged exception, " + consumerGroup, e.getMessage());
    }
}
 

import io.netty.channel.Channel; //導入依賴的package包/類
public List<String> getAllClientId() {
    List<String> result = new ArrayList<>();

    Iterator<Entry<Channel, ClientChannelInfo>> it = this.channelInfoTable.entrySet().iterator();

    while (it.hasNext()) {
        Entry<Channel, ClientChannelInfo> entry = it.next();
        ClientChannelInfo clientChannelInfo = entry.getValue();
        result.add(clientChannelInfo.getClientId());
    }

    return result;
}
 

import io.netty.channel.Channel; //導入依賴的package包/類
/**
 * 異步調用
 * @param channel
 * @param request
 * @param timeoutMillis
 * @param invokeCallback
 * @throws InterruptedException
 * @throws RemotingTooMuchRequestException
 * @throws RemotingTimeoutException
 * @throws RemotingSendRequestException
 */
@SuppressWarnings("rawtypes")
public void invokeAsyncImpl(final Channel channel, final RemotingProtocol request, final long timeoutMillis, final InvokeCallback invokeCallback) throws InterruptedException, RemotingTooMuchRequestException, RemotingTimeoutException, RemotingSendRequestException {
    final long opaque = request.getOpaque();
    //        boolean acquired = this.semaphoreAsync.tryAcquire(timeoutMillis, TimeUnit.MILLISECONDS);
    final SemaphoreOnce once = new SemaphoreOnce(this.semaphoreAsync);
    final ResponseFuture responseFuture = new ResponseFuture(opaque, timeoutMillis, invokeCallback, once);
    responseTable.put(opaque, responseFuture);
    try {
        channel.writeAndFlush(request).addListener(new ChannelFutureListener() {
            @Override
            public void operationComplete(ChannelFuture f) throws Exception {
                //此步代表發送操作成功   設置的sendrequest值是為了區分發送失敗還是服務端處理失敗的
                if (f.isSuccess()) {
                    responseFuture.setSendRequestOK(true);
                    return;
                } else {
                    responseFuture.setSendRequestOK(false);
                }
                responseFuture.putResponse(null);
                responseTable.remove(opaque);
                //                    try {
                //                        executeInvokeCallback(responseFuture);
                //                    } catch (Throwable e) {
                //                        logger.warn("excute callback in writeAndFlush addListener, and callback throw", e);
                //                    } finally {
                //                        responseFuture.release();
                //                    }
                logger.warn("send a request command to channel <{}> failed.", RemotingHelper.parseChannelRemoteAddr(channel));
            }
        });
    } catch (Exception e) {
        responseFuture.release();
        logger.warn("send a request command to channel <" + RemotingHelper.parseChannelRemoteAddr(channel) + "> Exception", e);
        throw new RemotingSendRequestException(RemotingHelper.parseChannelRemoteAddr(channel), e);
    }

}
 

import io.netty.channel.Channel; //導入依賴的package包/類
public static void registerClienId(String clientId, Channel chn) {
  if (chn == null) {
    return;
  }
  if (clientId == null) {
    return;
  }
  chn.closeFuture().addListener(clientRemover);
  channelClientIdMap.put(chn, clientId);
  ChannelEntity oldChannel = cientIdChannelMap.put(clientId, new TcpChannelEntity(chn));
  if (oldChannel != null) {
    removeChannel(oldChannel.getChannel());
    oldChannel.getChannel().close();
  }
}