List of usage examples for java.nio.channels DatagramChannel write
public final long write(ByteBuffer[] srcs) throws IOException
From source file:MainClass.java
public static void main(String[] args) throws IOException { DatagramChannel channel = DatagramChannel.open(); SocketAddress address = new InetSocketAddress(0); DatagramSocket socket = channel.socket(); socket.bind(address);/*w w w . j a va 2 s. c om*/ SocketAddress server = new InetSocketAddress("time-a.nist.gov", 37); channel.connect(server); ByteBuffer buffer = ByteBuffer.allocate(8); buffer.order(ByteOrder.BIG_ENDIAN); // send a byte of data to the server buffer.put((byte) 0); buffer.flip(); channel.write(buffer); // get the buffer ready to receive data buffer.clear(); // fill the first four bytes with zeros buffer.putInt(0); channel.read(buffer); buffer.flip(); // convert seconds since 1900 to a java.util.Date long secondsSince1900 = buffer.getLong(); long differenceBetweenEpochs = 2208988800L; long secondsSince1970 = secondsSince1900 - differenceBetweenEpochs; long msSince1970 = secondsSince1970 * 1000; Date time = new Date(msSince1970); System.out.println(time); }
From source file:org.openhab.binding.keba.handler.KeContactHandler.java
protected void onWritable(ByteBuffer buffer, DatagramChannel theChannel) { lock.lock();//from w ww .jav a 2 s .c om try { SelectionKey theSelectionKey = theChannel.keyFor(selector); if (theSelectionKey != null) { synchronized (selector) { try { selector.selectNow(); } catch (IOException e) { logger.error("An exception occurred while selecting: {}", e.getMessage()); } } Iterator<SelectionKey> it = selector.selectedKeys().iterator(); while (it.hasNext()) { SelectionKey selKey = it.next(); it.remove(); if (selKey.isValid() && selKey.isWritable() && selKey == theSelectionKey) { boolean error = false; buffer.rewind(); try { logger.debug("Sending '{}' on the channel '{}'->'{}'", new Object[] { new String(buffer.array()), theChannel.getLocalAddress(), theChannel.getRemoteAddress() }); theChannel.write(buffer); } catch (NotYetConnectedException e) { updateStatus(ThingStatus.OFFLINE, ThingStatusDetail.COMMUNICATION_ERROR, "The remote host is not yet connected"); error = true; } catch (ClosedChannelException e) { updateStatus(ThingStatus.OFFLINE, ThingStatusDetail.COMMUNICATION_ERROR, "The connection to the remote host is closed"); error = true; } catch (IOException e) { updateStatus(ThingStatus.OFFLINE, ThingStatusDetail.COMMUNICATION_ERROR, "An IO exception occurred"); error = true; } if (error) { logger.debug("Disconnecting '{}' because of a socket error", getThing().getUID().toString()); try { theChannel.close(); } catch (IOException e) { logger.warn("An exception occurred while closing the channel '{}': {}", datagramChannel, e.getMessage()); } onConnectionLost(); } } } } } finally { lock.unlock(); } }
From source file:org.openhab.binding.keba.handler.KeContactP20Handler.java
protected void onWritable(ByteBuffer buffer, DatagramChannel theChannel) { lock.lock();// w w w .j av a2 s. com try { SelectionKey theSelectionKey = theChannel.keyFor(selector); if (theSelectionKey != null) { synchronized (selector) { try { selector.selectNow(); } catch (IOException e) { logger.error("An exception occurred while selecting: {}", e.getMessage()); } } Iterator<SelectionKey> it = selector.selectedKeys().iterator(); while (it.hasNext()) { SelectionKey selKey = (SelectionKey) it.next(); it.remove(); if (selKey.isValid() && selKey.isWritable() && selKey == theSelectionKey) { boolean error = false; buffer.rewind(); try { logger.debug("Sending '{}' on the channel '{}'->'{}'", new Object[] { new String(buffer.array()), theChannel.getLocalAddress(), theChannel.getRemoteAddress() }); theChannel.write(buffer); } catch (NotYetConnectedException e) { updateStatus(ThingStatus.OFFLINE, ThingStatusDetail.COMMUNICATION_ERROR, "The remote host is not yet connected"); error = true; } catch (ClosedChannelException e) { updateStatus(ThingStatus.OFFLINE, ThingStatusDetail.COMMUNICATION_ERROR, "The connection to the remote host is closed"); error = true; } catch (IOException e) { updateStatus(ThingStatus.OFFLINE, ThingStatusDetail.COMMUNICATION_ERROR, "An IO exception occurred"); error = true; } if (error) { logger.debug("Disconnecting '{}' because of a socket error", getThing().getUID().toString()); try { theChannel.close(); } catch (IOException e) { logger.warn("An exception occurred while closing the channel '{}': {}", datagramChannel, e.getMessage()); } onConnectionLost(); } } } } } finally { lock.unlock(); } }
From source file:org.openhab.binding.mart.handler.martHandler.java
/** * this function reads from a buffer and writes into a channel * A buffer is essentially a block of memory into which you can write data, which * you can then later read again//from ww w. j a v a2 s .com * * @param buffer * @param theChannel */ protected void writer(ByteBuffer buffer, DatagramChannel theChannel) { lock.lock(); try { // represents the key representing the channel's registration with the Selector (selector). SelectionKey theSelectionKey = theChannel.keyFor(selector); // check if the key isn't null if (theSelectionKey != null) { synchronized (selector) { try { // selects a set of keys whose corresponding channels are ready // for I/O operations selector.selectNow(); } catch (IOException e) { logger.error("An exception occured while selecting {}", e.getMessage()); } } // returns this selector's selected-key set Iterator<SelectionKey> iterate = selector.selectedKeys().iterator(); while (iterate.hasNext()) { SelectionKey selectKey = iterate.next(); iterate.remove(); // checks if the key is valid // tests whether this channels is ready for writing // checks whether the current select key is equal to the channel's registered key // with the selector if (selectKey.isValid() && selectKey.isWritable() && selectKey == theSelectionKey) { boolean error = false; // sets the position back to 0, so you can reread all the data in the buffer buffer.rewind(); try { logger.debug("Sending '{}' in the channel '{}'->'{}'", new Object[] { new String(buffer.array()), theChannel.getLocalAddress(), theChannel.getRemoteAddress() }); // www.businessdictionary.com/definition/datagram.html // writes a datagram to this channel theChannel.write(buffer); } catch (NotYetConnectedException e) { updateStatus(ThingStatus.OFFLINE, ThingStatusDetail.COMMUNICATION_ERROR, "The remote host is not yet connected"); error = true; } catch (ClosedChannelException e) { updateStatus(ThingStatus.OFFLINE, ThingStatusDetail.COMMUNICATION_ERROR, "The connection to the remote host is closed"); error = true; } catch (IOException e) { updateStatus(ThingStatus.OFFLINE, ThingStatusDetail.COMMUNICATION_ERROR, "An Io exception occurred"); error = true; } if (error) { try { // closes the channel if it hasn't being closed already theChannel.close(); } catch (Exception e) { logger.warn("An exception occured while closing the channel '{}': {}", datagramChannel, e.getMessage()); } } // re-establish connection onConnectionLost(); } } } } finally { lock.unlock(); } }
From source file:org.openhab.binding.tcp.AbstractDatagramChannelBinding.java
/** * @{inheritDoc}// www . j a v a 2 s . co m */ @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); } } } } } } } }