List of usage examples for java.nio.channels DatagramChannel register
public final SelectionKey register(Selector sel, int ops) throws ClosedChannelException
From source file:DaytimeServer.java
public static void main(String args[]) { try { // Handle startup exceptions at the end of this block // Get an encoder for converting strings to bytes CharsetEncoder encoder = Charset.forName("US-ASCII").newEncoder(); // Allow an alternative port for testing with non-root accounts int port = 13; // RFC867 specifies this port. if (args.length > 0) port = Integer.parseInt(args[0]); // The port we'll listen on SocketAddress localport = new InetSocketAddress(port); // Create and bind a tcp channel to listen for connections on. ServerSocketChannel tcpserver = ServerSocketChannel.open(); tcpserver.socket().bind(localport); // Also create and bind a DatagramChannel to listen on. DatagramChannel udpserver = DatagramChannel.open(); udpserver.socket().bind(localport); // Specify non-blocking mode for both channels, since our // Selector object will be doing the blocking for us. tcpserver.configureBlocking(false); udpserver.configureBlocking(false); // The Selector object is what allows us to block while waiting // for activity on either of the two channels. Selector selector = Selector.open(); // Register the channels with the selector, and specify what // conditions (a connection ready to accept, a datagram ready // to read) we'd like the Selector to wake up for. // These methods return SelectionKey objects, which we don't // need to retain in this example. tcpserver.register(selector, SelectionKey.OP_ACCEPT); udpserver.register(selector, SelectionKey.OP_READ); // This is an empty byte buffer to receive emtpy datagrams with. // If a datagram overflows the receive buffer size, the extra bytes // are automatically discarded, so we don't have to worry about // buffer overflow attacks here. ByteBuffer receiveBuffer = ByteBuffer.allocate(0); // Now loop forever, processing client connections for (;;) { try { // Handle per-connection problems below // Wait for a client to connect selector.select();//from w w w. j av a 2 s.c om // If we get here, a client has probably connected, so // put our response into a ByteBuffer. String date = new java.util.Date().toString() + "\r\n"; ByteBuffer response = encoder.encode(CharBuffer.wrap(date)); // Get the SelectionKey objects for the channels that have // activity on them. These are the keys returned by the // register() methods above. They are returned in a // java.util.Set. Set keys = selector.selectedKeys(); // Iterate through the Set of keys. for (Iterator i = keys.iterator(); i.hasNext();) { // Get a key from the set, and remove it from the set SelectionKey key = (SelectionKey) i.next(); i.remove(); // Get the channel associated with the key Channel c = (Channel) key.channel(); // Now test the key and the channel to find out // whether something happend on the TCP or UDP channel if (key.isAcceptable() && c == tcpserver) { // A client has attempted to connect via TCP. // Accept the connection now. SocketChannel client = tcpserver.accept(); // If we accepted the connection successfully, // the send our respone back to the client. if (client != null) { client.write(response); // send respone client.close(); // close connection } } else if (key.isReadable() && c == udpserver) { // A UDP datagram is waiting. Receive it now, // noting the address it was sent from. SocketAddress clientAddress = udpserver.receive(receiveBuffer); // If we got the datagram successfully, send // the date and time in a response packet. if (clientAddress != null) udpserver.send(response, clientAddress); } } } catch (java.io.IOException e) { // This is a (hopefully transient) problem with a single // connection: we log the error, but continue running. // We use our classname for the logger so that a sysadmin // can configure logging for this server independently // of other programs. Logger l = Logger.getLogger(DaytimeServer.class.getName()); l.log(Level.WARNING, "IOException in DaytimeServer", e); } catch (Throwable t) { // If anything else goes wrong (out of memory, for example) // then log the problem and exit. Logger l = Logger.getLogger(DaytimeServer.class.getName()); l.log(Level.SEVERE, "FATAL error in DaytimeServer", t); System.exit(1); } } } catch (Exception e) { // This is a startup error: there is no need to log it; // just print a message and exit System.err.println(e); System.exit(1); } }
From source file:com.offbynull.portmapper.common.UdpCommunicator.java
@Override protected void startUp() throws Exception { selector = Selector.open();//from w w w .jav a 2 s .com for (DatagramChannel channel : sendQueue.keySet()) { channel.register(selector, SelectionKey.OP_READ); } }
From source file:me.schiz.jmeter.ring.udp.EventLoopRunnable.java
private void registerCallback(int register_count) { for (int i = 0; i < Math.min(register_count, REGS_PER_ITERATION); i++) { KeyValue kv = registerQueue.poll(); if (kv == null) break; if (kv.key instanceof DatagramChannel && kv.value instanceof Integer) { DatagramChannel dc = (DatagramChannel) kv.key; int ops = (Integer) kv.value; try { dc.register(selector, ops); } catch (ClosedSelectorException e) { log.error("Selector is closed", e); break; } catch (CancelledKeyException e) { log.error("", e); } catch (ClosedChannelException e) { log.warn("", e); Token t = ring.get(dc);/*from w ww.j a va2 s . c om*/ if (t != null) ring.reset(t.id); } } } }
From source file:com.offbynull.portmapper.common.UdpCommunicator.java
@Override protected void run() throws Exception { ByteBuffer recvBuffer = ByteBuffer.allocate(1100); while (true) { selector.select();//from w w w . j av a 2 s .co m if (stopFlag) { return; } for (DatagramChannel channel : sendQueue.keySet()) { if (!sendQueue.get(channel).isEmpty()) { channel.register(selector, SelectionKey.OP_READ | SelectionKey.OP_WRITE); } else { channel.register(selector, SelectionKey.OP_READ); } } for (SelectionKey key : selector.selectedKeys()) { if (!key.isValid()) { continue; } DatagramChannel channel = (DatagramChannel) key.channel(); if (key.isReadable()) { recvBuffer.clear(); InetSocketAddress incomingAddress = (InetSocketAddress) channel.receive(recvBuffer); recvBuffer.flip(); for (UdpCommunicatorListener listener : listeners) { try { listener.incomingPacket(incomingAddress, channel, recvBuffer.asReadOnlyBuffer()); } catch (RuntimeException re) { // NOPMD // do nothing } } } else if (key.isWritable()) { LinkedBlockingQueue<ImmutablePair<InetSocketAddress, ByteBuffer>> queue = sendQueue .get(channel); ImmutablePair<InetSocketAddress, ByteBuffer> next = queue.poll(); if (next != null) { try { channel.send(next.getValue(), next.getKey()); } catch (RuntimeException re) { // NOPMD // do nothing } } } } } }
From source file:org.apache.nifi.io.nio.ChannelListener.java
/** * Binds to listen for data grams on the given local IPAddress/port * * @param nicIPAddress - if null will listen on wildcard address, which * means datagrams will be received on all local network interfaces. * Otherwise, will bind to the provided IP address associated with some NIC. * @param port - the port to listen on// w w w . ja v a 2 s. c o m * @param receiveBufferSize - the number of bytes to request for a receive * buffer from OS * @throws IOException if unable to add channel */ public void addDatagramChannel(final InetAddress nicIPAddress, final int port, final int receiveBufferSize) throws IOException { final DatagramChannel dChannel = createAndBindDatagramChannel(nicIPAddress, port, receiveBufferSize); dChannel.register(socketChannelSelector, SelectionKey.OP_READ); }
From source file:org.apache.nifi.io.nio.ChannelListener.java
/** * Binds to listen for data grams on the given local IPAddress/port and * restricts receipt of datagrams to those from the provided host and port, * must specify both. This improves performance for datagrams coming from a * sender that is known a-priori.// w w w .j av a 2 s. c o m * * @param nicIPAddress - if null will listen on wildcard address, which * means datagrams will be received on all local network interfaces. * Otherwise, will bind to the provided IP address associated with some NIC. * @param port - the port to listen on. This is used to provide a well-known * destination for a sender. * @param receiveBufferSize - the number of bytes to request for a receive * buffer from OS * @param sendingHost - the hostname, or IP address, of the sender of * datagrams. Only datagrams from this host will be received. If this is * null the wildcard ip is used, which means datagrams may be received from * any network interface on the local host. * @param sendingPort - the port used by the sender of datagrams. Only * datagrams from this port will be received. * @throws IOException if unable to add channel */ public void addDatagramChannel(final InetAddress nicIPAddress, final int port, final int receiveBufferSize, final String sendingHost, final Integer sendingPort) throws IOException { if (sendingHost == null || sendingPort == null) { addDatagramChannel(nicIPAddress, port, receiveBufferSize); return; } final DatagramChannel dChannel = createAndBindDatagramChannel(nicIPAddress, port, receiveBufferSize); dChannel.connect(new InetSocketAddress(sendingHost, sendingPort)); dChannel.register(socketChannelSelector, SelectionKey.OP_READ); }
From source file:org.openhab.binding.tcp.AbstractDatagramChannelBinding.java
/** * @{inheritDoc}// w ww . j a v a 2 s . c om */ @Override protected void execute() { // Cycle through the Items and setup channels if required for (P provider : providers) { for (String itemName : provider.getItemNames()) { for (Command aCommand : ((P) provider).getAllCommands(itemName)) { String remoteHost = ((P) provider).getHost(itemName, aCommand); String remotePort = ((P) provider).getPortAsString(itemName, aCommand); Direction direction = ((P) provider).getDirection(itemName, aCommand); InetSocketAddress remoteAddress = null; if (!(remoteHost.equals("*") || remotePort.equals("*"))) { remoteAddress = new InetSocketAddress(remoteHost, Integer.parseInt(remotePort)); } Channel newChannel = null; Channel existingChannel = null; if (useAddressMask && (remoteHost.equals("*") || remotePort.equals("*"))) { newChannel = new Channel(itemName, aCommand, remoteHost, remotePort, ((P) provider).getDirection(itemName, aCommand), false, null, false, null); existingChannel = channels.get(itemName, aCommand, direction, remoteHost, remotePort); } else { newChannel = new Channel(itemName, aCommand, remoteAddress, ((P) provider).getDirection(itemName, aCommand), false, null, false, null); existingChannel = channels.get(itemName, aCommand, direction, remoteAddress); } if (existingChannel == null) { if (direction == Direction.IN) { boolean assigned = false; if (useAddressMask && (remoteHost.equals("*") || remotePort.equals("*"))) { logger.warn( "When using address masks we will not verify if we are already listening to similar incoming connections"); logger.info("We will accept data coming from the remote end {}:{}", remoteHost, remotePort); } else { if (channels.contains(itemName, aCommand, Direction.IN, remoteAddress)) { logger.warn("We already listen for incoming connections from {}", remoteAddress); } else { if (itemShareChannels) { Channel firstChannel = channels.getFirstServed(itemName, direction, remoteAddress); if (firstChannel != null) { newChannel.channel = firstChannel.channel; assigned = true; } } if (bindingShareChannels) { Channel firstChannel = channels.getFirstServed(direction, remoteAddress); if (firstChannel != null) { newChannel.channel = firstChannel.channel; assigned = true; } } if (directionsShareChannels) { Channel firstChannel = channels.getFirstServed(remoteAddress); if (firstChannel != null) { newChannel.channel = firstChannel.channel; assigned = true; } } } } if (!assigned) { newChannel.channel = listenerChannel; } if (useAddressMask && (remoteHost.equals("*") || remotePort.equals("*"))) { logger.info("We will accept data coming from the remote end with mask {}:{}", remoteHost, remotePort); } else { logger.info("We will accept data coming from the remote end {}", remoteAddress); } logger.debug("Setting up the inbound channel {}", newChannel); channels.add(newChannel); } else if (direction == Direction.OUT) { boolean assigned = false; if (useAddressMask && (remoteHost.equals("*") || remotePort.equals("*"))) { logger.error( "We do not accept outgoing connections for Items that do use address masks"); } else { channels.add(newChannel); if (newChannel.channel == null) { if (itemShareChannels) { Channel firstChannel = channels.getFirstServed(itemName, direction, remoteAddress); if (firstChannel != null) { newChannel.channel = firstChannel.channel; assigned = true; } } if (bindingShareChannels) { Channel firstChannel = channels.getFirstServed(direction, remoteAddress); if (firstChannel != null) { newChannel.channel = firstChannel.channel; assigned = true; } } // I think it is better not to share incoming connections with outgoing connections (in the case of the // UDP binding) // if(directionsShareChannels) { // Channel firstChannel = channels.getFirstServed(remoteAddress); // if(firstChannel != null) { // newChannel.channel = firstChannel.channel; // assigned = true; // } // if (assigned) { logger.debug("Setting up the outbound assigned channel {} ", newChannel); } } synchronized (this) { if (!assigned || newChannel.channel == null) { DatagramChannel newDatagramChannel = null; try { newDatagramChannel = DatagramChannel.open(); } catch (IOException e2) { logger.error("An exception occurred while opening a channel: {}", e2.getMessage()); } try { newDatagramChannel.configureBlocking(false); //setKeepAlive(true); } catch (IOException e) { logger.error("An exception occurred while configuring a channel: {}", e.getMessage()); } synchronized (selector) { selector.wakeup(); try { newDatagramChannel.register(selector, newDatagramChannel.validOps()); } catch (ClosedChannelException e1) { logger.error( "An exception occurred while registering a selector: {}", e1.getMessage()); } } newChannel.channel = newDatagramChannel; logger.debug("Setting up the outbound channel {}", newChannel); try { logger.info("'Connecting' the channel {} ", newChannel); newDatagramChannel.connect(remoteAddress); } catch (IOException e) { logger.error("An exception occurred while connecting a channel: {}", e.getMessage()); } } else { logger.info("There is already an active channel {} for the remote end {}", newChannel.channel, newChannel.remote); } } } } } } } } // Check on channels for which we have to process data synchronized (selector) { try { // Wait for an event selector.selectNow(); } catch (IOException e) { logger.error("An exception occurred while Selecting ({})", e.getMessage()); } } // Get list of selection keys with pending events Iterator<SelectionKey> it = selector.selectedKeys().iterator(); // Process each key at a time while (it.hasNext()) { SelectionKey selKey = (SelectionKey) it.next(); it.remove(); if (selKey.isValid()) { DatagramChannel theDatagramChannel = (DatagramChannel) selKey.channel(); Channel theChannel = channels.get(theDatagramChannel); if (selKey.isReadable()) { InetSocketAddress clientAddress = null; ByteBuffer readBuffer = ByteBuffer.allocate(maximumBufferSize); int numberBytesRead = 0; boolean error = false; if (selKey == listenerKey) { try { clientAddress = (InetSocketAddress) theDatagramChannel.receive(readBuffer); logger.debug("Received {} on the listener port from {}", new String(readBuffer.array()), clientAddress); numberBytesRead = readBuffer.position(); } catch (Exception e) { error = true; } } else { try { //TODO: Additional code to split readBuffer in multiple parts, in case the data send by the remote end is not correctly fragemented. Could be handed of to implementation class if for example, the buffer needs to be split based on a special character like line feed or carriage return numberBytesRead = theDatagramChannel.read(readBuffer); logger.debug("Received {} bytes ({}) on the channel {}->{}", new Object[] { numberBytesRead, new String(readBuffer.array()), theDatagramChannel.getLocalAddress(), theDatagramChannel.getRemoteAddress() }); } catch (NotYetConnectedException e) { try { logger.warn("The channel for {} has no connection pending ({})", theDatagramChannel.getRemoteAddress(), e.getMessage()); } catch (IOException e1) { logger.error( "An exception occurred while getting the remote address of channel {} ({})", theDatagramChannel, e1.getMessage()); } error = true; } catch (IOException e) { // If some other I/O error occurs try { logger.warn("The channel for {} has encountered an unknown IO Exception: {}", theDatagramChannel.getRemoteAddress(), e.getMessage()); } catch (IOException e1) { logger.error( "An exception occurred while getting the remote address of channel {} ({})", theDatagramChannel, e1.getMessage()); } error = true; } } if (numberBytesRead == -1) { try { if (selKey != listenerKey) { theDatagramChannel.close(); } } catch (IOException e) { try { logger.warn("The channel for {} is closed ({})", theDatagramChannel.getRemoteAddress(), e.getMessage()); } catch (IOException e1) { logger.error( "An exception occurred while getting the remote address of channel {} ({})", theDatagramChannel, e1.getMessage()); } } error = true; } if (error) { if (selKey != listenerKey) { Scheduler scheduler = null; try { scheduler = StdSchedulerFactory.getDefaultScheduler(); } catch (SchedulerException e1) { logger.error("An exception occurred while getting the Quartz scheduler: {}", e1.getMessage()); } JobDataMap map = new JobDataMap(); map.put("Channel", theChannel); map.put("Binding", this); JobDetail job = null; Trigger trigger = null; job = newJob(ReconnectJob.class) .withIdentity(Integer.toHexString(hashCode()) + "-Reconnect-" + Long.toString(System.currentTimeMillis()), this.toString()) .usingJobData(map).build(); trigger = newTrigger() .withIdentity(Integer.toHexString(hashCode()) + "-Reconnect-" + Long.toString(System.currentTimeMillis()), this.toString()) .startAt(futureDate(reconnectInterval, IntervalUnit.SECOND)).build(); try { if (job != null && trigger != null && selKey != listenerKey) { if (!theChannel.isReconnecting) { channels.setAllReconnecting(theDatagramChannel, true); scheduler.scheduleJob(job, trigger); } } } catch (SchedulerException e) { logger.error( "An exception occurred while scheduling a job with the Quartz Scheduler {}", e.getMessage()); } } } else { ArrayList<Channel> channelsToServe = new ArrayList<Channel>(); if (selKey == listenerKey) { channelsToServe = channels.getAll(Direction.IN, clientAddress); if (channelsToServe.size() == 0) { logger.warn( "Received data {} from an undefined remote end {}. We will not process it", new String(readBuffer.array()), clientAddress); } } else { channelsToServe = channels.getAll(theDatagramChannel); } if (channelsToServe.size() > 0) { readBuffer.flip(); if (channels.isBlocking(theDatagramChannel)) { // if we are in a blocking operation, we get are now finished and we have to reset the flag. The read buffer will be returned to the instance // that initiated the write opreation - it has to parse the buffer itself //find the Channel with this DGC that is holding a Blocking flag theChannel = channels.getBlocking(theDatagramChannel); theChannel.buffer = readBuffer; } else { for (Channel aChannel : channelsToServe) { if (useAddressMask) { aChannel.lastRemote = clientAddress; } // if not, then we parse the buffer as ususal parseChanneledBuffer(aChannel, readBuffer); } } } else { try { if (selKey == listenerKey) { logger.warn( "No channel is active or defined for the data we received from {}. It will be discarded.", clientAddress); } else { logger.warn( "No channel is active or defined for the data we received from {}. It will be discarded.", theDatagramChannel.getRemoteAddress()); } } catch (IOException e) { logger.error( "An exception occurred while getting the remote address of channel {} ({})", theDatagramChannel, e.getMessage()); } } } } else if (selKey.isWritable()) { WriteBufferElement theElement = null; if (selKey == listenerKey) { Iterator<WriteBufferElement> iterator = writeQueue.iterator(); while (iterator.hasNext()) { WriteBufferElement anElement = iterator.next(); if (anElement.channel.channel.equals(listenerChannel)) { theElement = anElement; break; } } } //check if any of the Channel using the DatagramChannel is blocking the DGC in a R/W operation boolean isBlocking = channels.isBlocking(theDatagramChannel); if (isBlocking) { // if this channel is already flagged as being in a blocked write/read operation, we skip this selKey } else { if (selKey != listenerKey) { Iterator<WriteBufferElement> iterator = writeQueue.iterator(); while (iterator.hasNext()) { WriteBufferElement anElement = iterator.next(); if (anElement.channel.channel.equals(theDatagramChannel)) { theElement = anElement; break; } } } if (theElement != null && theElement.buffer != null) { logger.debug("Picked {} from the queue", theElement); if (theElement.isBlocking) { theElement.channel.isBlocking = true; } boolean error = false; theElement.buffer.rewind(); if (selKey == listenerKey) { try { if (useAddressMask && theElement.channel.remote == null) { if (theElement.channel.lastRemote != null) { logger.debug( "Sending {} for the masked inbound channel {}:{} to the remote address {}", new Object[] { new String(theElement.buffer.array()), theElement.channel.host, theElement.channel.port, theElement.channel.lastRemote }); listenerChannel.send(theElement.buffer, theElement.channel.lastRemote); } else { logger.warn("I do not know where to send the data {}", new String(theElement.buffer.array())); } } else { logger.debug( "Sending {} for the inbound channel {}:{} to the remote address {}", new Object[] { new String(theElement.buffer.array()), theElement.channel.host, theElement.channel.port, theElement.channel.remote }); listenerChannel.send(theElement.buffer, theElement.channel.remote); } } catch (IOException e) { if (theElement.channel.lastRemote != null) { logger.error( "An exception occurred while sending data to the remote end {} ({})", theElement.channel.lastRemote, e.getMessage()); } else { logger.error( "An exception occurred while sending data to the remote end {} ({})", theElement.channel.remote, e.getMessage()); } } } else { try { logger.debug( "Sending {} for the outbound channel {}:{} to the remote address {}", new Object[] { new String(theElement.buffer.array()), theElement.channel.host, theElement.channel.port, theElement.channel.remote }); theDatagramChannel.write(theElement.buffer); } catch (NotYetConnectedException e) { logger.warn("The channel for {} has no connection pending ({})", theElement.channel.remote, e.getMessage()); error = true; } catch (ClosedChannelException e) { // If some other I/O error occurs logger.warn("The channel for {} is closed ({})", theElement.channel.remote, e.getMessage()); error = true; } catch (IOException e) { // If some other I/O error occurs logger.warn("The channel for {} has encountered an unknown IO Exception: {}", theElement.channel.remote, e.getMessage()); error = true; } } if (error) { if (selKey != listenerKey) { Scheduler scheduler = null; try { scheduler = StdSchedulerFactory.getDefaultScheduler(); } catch (SchedulerException e1) { logger.error("An exception occurred while getting the Quartz scheduler: {}", e1.getMessage()); } JobDataMap map = new JobDataMap(); map.put("Channel", theElement.channel); map.put("Binding", this); JobDetail job = null; Trigger trigger = null; job = newJob(ReconnectJob.class) .withIdentity( Integer.toHexString(hashCode()) + "-Reconnect-" + Long.toString(System.currentTimeMillis()), this.toString()) .usingJobData(map).build(); trigger = newTrigger() .withIdentity( Integer.toHexString(hashCode()) + "-Reconnect-" + Long.toString(System.currentTimeMillis()), this.toString()) .startAt(futureDate(reconnectInterval, IntervalUnit.SECOND)).build(); try { if (job != null && trigger != null && selKey != listenerKey) { if (!theElement.channel.isReconnecting) { channels.setAllReconnecting(theElement.channel.channel, true); scheduler.scheduleJob(job, trigger); } } } catch (SchedulerException e) { logger.error( "An exception occurred while scheduling a job with the Quartz Scheduler {}", e.getMessage()); } } } else { if (theElement != null) { writeQueue.remove(theElement); } } } } } } } }