Examples with Selector java.nio.channels.Selector used on opensource projects

Example 51 with Selector

use of java.nio.channels.Selector in project tomcat by apache.

the class NioReceiver method listen.

/**
     * Get data from channel and store in byte array
     * send it to cluster
     * @throws IOException IO error
     */
protected void listen() throws Exception {
    if (doListen()) {
        log.warn(sm.getString("nioReceiver.alreadyStarted"));
        return;
    }
    setListen(true);
    // Avoid NPEs if selector is set to null on stop.
    Selector selector = this.selector.get();
    if (selector != null && datagramChannel != null) {
        //max size for a datagram packet
        ObjectReader oreader = new ObjectReader(MAX_UDP_SIZE);
        registerChannel(selector, datagramChannel, SelectionKey.OP_READ, oreader);
    }
    while (doListen() && selector != null) {
        // selected set contains keys of the ready channels
        try {
            events();
            socketTimeouts();
            int n = selector.select(getSelectorTimeout());
            if (n == 0) {
                // nothing to do
                continue;
            }
            // get an iterator over the set of selected keys
            Iterator<SelectionKey> it = selector.selectedKeys().iterator();
            // look at each key in the selected set
            while (it != null && it.hasNext()) {
                SelectionKey key = it.next();
                // Is a new connection coming in?
                if (key.isAcceptable()) {
                    ServerSocketChannel server = (ServerSocketChannel) key.channel();
                    SocketChannel channel = server.accept();
                    channel.socket().setReceiveBufferSize(getTxBufSize());
                    channel.socket().setSendBufferSize(getTxBufSize());
                    channel.socket().setTcpNoDelay(getTcpNoDelay());
                    channel.socket().setKeepAlive(getSoKeepAlive());
                    channel.socket().setOOBInline(getOoBInline());
                    channel.socket().setReuseAddress(getSoReuseAddress());
                    channel.socket().setSoLinger(getSoLingerOn(), getSoLingerTime());
                    channel.socket().setSoTimeout(getTimeout());
                    Object attach = new ObjectReader(channel);
                    registerChannel(selector, channel, SelectionKey.OP_READ, attach);
                }
                // is there data to read on this channel?
                if (key.isReadable()) {
                    readDataFromSocket(key);
                } else {
                    key.interestOps(key.interestOps() & (~SelectionKey.OP_WRITE));
                }
                // remove key from selected set, it's been handled
                it.remove();
            }
        } catch (java.nio.channels.ClosedSelectorException cse) {
        // ignore is normal at shutdown or stop listen socket
        } catch (java.nio.channels.CancelledKeyException nx) {
            log.warn(sm.getString("nioReceiver.clientDisconnect"));
        } catch (Throwable t) {
            ExceptionUtils.handleThrowable(t);
            log.error(sm.getString("nioReceiver.requestError"), t);
        }
    }
    serverChannel.close();
    if (datagramChannel != null) {
        try {
            datagramChannel.close();
        } catch (Exception iox) {
            if (log.isDebugEnabled())
                log.debug("Unable to close datagram channel.", iox);
        }
        datagramChannel = null;
    }
    closeSelector();
}

Example 52 with Selector

use of java.nio.channels.Selector in project tomcat by apache.

the class NioChannel method getAttachment.

public Object getAttachment() {
    Poller pol = getPoller();
    Selector sel = pol != null ? pol.getSelector() : null;
    SelectionKey key = sel != null ? getIOChannel().keyFor(sel) : null;
    Object att = key != null ? key.attachment() : null;
    return att;
}

Example 53 with Selector

use of java.nio.channels.Selector in project hs4j by killme2008.

the class NioTCPSession method blockingWrite.

/**
	 * Blocking write using temp selector
	 * 
	 * @param channel
	 * @param message
	 * @param writeBuffer
	 * @return
	 * @throws IOException
	 * @throws ClosedChannelException
	 */
protected final Object blockingWrite(SelectableChannel channel, WriteMessage message, IoBuffer writeBuffer) throws IOException, ClosedChannelException {
    SelectionKey tmpKey = null;
    Selector writeSelector = null;
    int attempts = 0;
    int bytesProduced = 0;
    try {
        while (writeBuffer.hasRemaining()) {
            long len = doRealWrite(channel, writeBuffer);
            if (len > 0) {
                attempts = 0;
                bytesProduced += len;
                statistics.statisticsWrite(len);
            } else {
                attempts++;
                if (writeSelector == null) {
                    writeSelector = SelectorFactory.getSelector();
                    if (writeSelector == null) {
                        // Continue using the main one.
                        continue;
                    }
                    tmpKey = channel.register(writeSelector, SelectionKey.OP_WRITE);
                }
                if (writeSelector.select(1000) == 0) {
                    if (attempts > 2) {
                        throw new IOException("Client disconnected");
                    }
                }
            }
        }
        if (!writeBuffer.hasRemaining() && message.getWriteFuture() != null) {
            message.getWriteFuture().setResult(Boolean.TRUE);
        }
    } finally {
        if (tmpKey != null) {
            tmpKey.cancel();
            tmpKey = null;
        }
        if (writeSelector != null) {
            // Cancel the key.
            writeSelector.selectNow();
            SelectorFactory.returnSelector(writeSelector);
        }
    }
    scheduleWritenBytes.addAndGet(0 - bytesProduced);
    return message.getMessage();
}

Example 54 with Selector

use of java.nio.channels.Selector in project hs4j by killme2008.

the class Reactor method unregisterChannel.

final void unregisterChannel(SelectableChannel channel) throws IOException {
    Selector selector = this.selector;
    if (selector != null) {
        if (channel != null) {
            SelectionKey key = channel.keyFor(selector);
            if (key != null) {
                key.cancel();
            }
        }
    }
    wakeup();
}

Example 55 with Selector

use of java.nio.channels.Selector in project hs4j by killme2008.

the class Reactor method lookJVMBug.

/**
	 * Look jvm bug
	 * 
	 * @param before
	 * @param selected
	 * @param wait
	 * @return
	 * @throws IOException
	 */
private boolean lookJVMBug(long before, int selected, long wait) throws IOException {
    boolean seeing = false;
    long now = System.currentTimeMillis();
    if (JVMBUG_THRESHHOLD > 0 && selected == 0 && wait > JVMBUG_THRESHHOLD && now - before < wait / 4 && !wakenUp.get() && /* waken up */
    !Thread.currentThread().isInterrupted()) /* Interrupted */
    {
        jvmBug.incrementAndGet();
        if (jvmBug.get() >= JVMBUG_THRESHHOLD2) {
            gate.lock();
            try {
                lastJVMBug = now;
                log.warn("JVM bug occured at " + new Date(lastJVMBug) + ",http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=6403933,reactIndex=" + reactorIndex);
                if (jvmBug1) {
                    log.debug("seeing JVM BUG(s) - recreating selector,reactIndex=" + reactorIndex);
                } else {
                    jvmBug1 = true;
                    log.info("seeing JVM BUG(s) - recreating selector,reactIndex=" + reactorIndex);
                }
                seeing = true;
                final Selector new_selector = SystemUtils.openSelector();
                for (SelectionKey k : selector.keys()) {
                    if (!k.isValid() || k.interestOps() == 0) {
                        continue;
                    }
                    final SelectableChannel channel = k.channel();
                    final Object attachment = k.attachment();
                    channel.register(new_selector, k.interestOps(), attachment);
                }
                selector.close();
                selector = new_selector;
            } finally {
                gate.unlock();
            }
            jvmBug.set(0);
        } else if (jvmBug.get() == JVMBUG_THRESHHOLD || jvmBug.get() == JVMBUG_THRESHHOLD1) {
            if (jvmBug0) {
                log.debug("seeing JVM BUG(s) - cancelling interestOps==0,reactIndex=" + reactorIndex);
            } else {
                jvmBug0 = true;
                log.info("seeing JVM BUG(s) - cancelling interestOps==0,reactIndex=" + reactorIndex);
            }
            gate.lock();
            seeing = true;
            try {
                for (SelectionKey k : selector.keys()) {
                    if (k.isValid() && k.interestOps() == 0) {
                        k.cancel();
                    }
                }
            } finally {
                gate.unlock();
            }
        }
    } else {
        jvmBug.set(0);
    }
    return seeing;
}