Example usage for java.nio.channels DatagramChannel socket

List of usage examples for java.nio.channels DatagramChannel socket

  1. HOME
  2. Java
  3. java
  4. java.nio.channels.*
  5. DatagramChannel
  6. socket

Introduction

In this page you can find the example usage for java.nio.channels DatagramChannel socket.

Prototype

public abstract DatagramSocket socket();

Source Link

Document

Retrieves a datagram socket associated with this channel.

Usage

From source file:MainClass.java

public static void main(String[] args) throws Exception {
    DatagramChannel channel = DatagramChannel.open();
    DatagramSocket socket = channel.socket();
    SocketAddress address = new InetSocketAddress(9999);
    socket.bind(address);// w w w  . ja  v a 2 s .  com
    ByteBuffer buffer = ByteBuffer.allocateDirect(65507);
    while (true) {
        SocketAddress client = channel.receive(buffer);
        buffer.flip();
        channel.send(buffer, client);
        buffer.clear();
    }
}

From source file:UDPTimeServer.java

public static void main(String[] args) throws IOException {

    int port = 37;

    ByteBuffer in = ByteBuffer.allocate(8192);
    ByteBuffer out = ByteBuffer.allocate(8);
    out.order(ByteOrder.BIG_ENDIAN);
    SocketAddress address = new InetSocketAddress(port);
    DatagramChannel channel = DatagramChannel.open();
    DatagramSocket socket = channel.socket();
    socket.bind(address);//ww  w. j a  v a2s. c  o  m
    System.err.println("bound to " + address);
    while (true) {
        try {
            in.clear();
            SocketAddress client = channel.receive(in);
            System.err.println(client);
            long secondsSince1970 = System.currentTimeMillis();
            out.clear();
            out.putLong(secondsSince1970);
            out.flip();

            out.position(4);
            channel.send(out, client);
        } catch (Exception ex) {
            System.err.println(ex);
        }
    }
}

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);/*from  ww w.j  a v a 2 s  . c o  m*/

    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:UDPTimeClient.java

public static void main(String[] args) throws Exception {

    DatagramChannel channel = DatagramChannel.open();
    // port 0 selects any available port
    SocketAddress address = new InetSocketAddress(0);
    DatagramSocket socket = channel.socket();
    socket.setSoTimeout(5000);/*w  ww . j  av  a 2 s  .  c o m*/
    socket.bind(address);

    SocketAddress server = new InetSocketAddress("time.nist.gov", 37);
    ByteBuffer buffer = ByteBuffer.allocate(8192);
    // time protocol always uses big-endian order
    buffer.order(ByteOrder.BIG_ENDIAN);
    // Must put at least one byte of data in the buffer;
    // it doesn't matter what it is.
    buffer.put((byte) 65);
    buffer.flip();

    channel.send(buffer, server);

    buffer.clear();
    buffer.put((byte) 0).put((byte) 0).put((byte) 0).put((byte) 0);
    channel.receive(buffer);
    buffer.flip();
    long secondsSince1970 = buffer.getLong();

    System.out.println(secondsSince1970);
    channel.close();

}

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 ava  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.natpmp.NatPmpDiscovery.java

private static Set<InetAddress> discoverGateways() throws InterruptedException, IOException {
    final Set<InetAddress> foundGateways = Collections.synchronizedSet(new HashSet<InetAddress>());
    Set<InetAddress> potentialGateways = NetworkUtils.getPotentialGatewayAddresses(); // port 5351

    DatagramChannel unicastChannel = null;
    try {//from ww  w  .j  a v a  2 s .c  o m
        unicastChannel = DatagramChannel.open();
        unicastChannel.configureBlocking(false);
        unicastChannel.socket().bind(new InetSocketAddress(0));
    } catch (IOException ioe) {
        IOUtils.closeQuietly(unicastChannel);
        throw ioe;
    }

    UdpCommunicator communicator = null;
    try {
        communicator = new UdpCommunicator(Collections.singletonList(unicastChannel));
        communicator.startAsync().awaitRunning();
        communicator.addListener(new UdpCommunicatorListener() {

            @Override
            public void incomingPacket(InetSocketAddress sourceAddress, DatagramChannel channel,
                    ByteBuffer packet) {
                new ExternalAddressNatPmpResponse(packet); // should error out if not valid

                foundGateways.add(sourceAddress.getAddress());
            }
        });

        ByteBuffer outBuf = ByteBuffer.allocate(16);
        ExternalAddressNatPmpRequest eanpr = new ExternalAddressNatPmpRequest();
        eanpr.dump(outBuf);

        outBuf.flip();

        for (InetAddress potentialGateway : potentialGateways) {
            communicator.send(unicastChannel, new InetSocketAddress(potentialGateway, 5351),
                    outBuf.asReadOnlyBuffer());
        }

        Thread.sleep(5000L);
    } finally {
        if (communicator != null) {
            communicator.stopAsync().awaitTerminated();
        }
    }

    return new HashSet<>(foundGateways);
}

From source file:com.offbynull.portmapper.pcp.PcpDiscovery.java

private static Set<InetAddress> discoverGateways() throws InterruptedException, IOException {
    final Set<InetAddress> foundGateways = Collections.synchronizedSet(new HashSet<InetAddress>());
    Set<InetAddress> potentialGateways = NetworkUtils.getPotentialGatewayAddresses(); // port 5351

    DatagramChannel unicastChannel = null;
    try {//from  w w w.  ja va2  s  . co  m
        unicastChannel = DatagramChannel.open();
        unicastChannel.configureBlocking(false);
        unicastChannel.socket().bind(new InetSocketAddress(0));
    } catch (IOException ioe) {
        IOUtils.closeQuietly(unicastChannel);
        throw ioe;
    }

    UdpCommunicator communicator = null;
    try {
        communicator = new UdpCommunicator(Collections.singletonList(unicastChannel));
        communicator.startAsync().awaitRunning();
        communicator.addListener(new UdpCommunicatorListener() {

            @Override
            public void incomingPacket(InetSocketAddress sourceAddress, DatagramChannel channel,
                    ByteBuffer packet) {
                foundGateways.add(sourceAddress.getAddress());
            }
        });

        ByteBuffer outBuf = ByteBuffer.allocate(1100);
        MapPcpRequest mpr = new MapPcpRequest(ByteBuffer.allocate(12), 0, 0, 0, InetAddress.getByName("::"),
                0L);
        mpr.dump(outBuf, InetAddress.getByAddress(new byte[4])); // should get back an error for this, but this
                                                                 // should be fine because all we're looking for is a response, not
                                                                 // nessecarily a correct response -- self address being sent is
                                                                 // 0.0.0.0 (IPV4)
                                                                 //
                                                                 // also, we need to pass in MAP because Apple's garbage routers
                                                                 // give back NATPMP responses when you pass in ANNOUNCE

        outBuf.flip();

        for (InetAddress potentialGateway : potentialGateways) {
            communicator.send(unicastChannel, new InetSocketAddress(potentialGateway, 5351),
                    outBuf.asReadOnlyBuffer());
        }

        Thread.sleep(5000L);
    } finally {
        if (communicator != null) {
            communicator.stopAsync().awaitTerminated();
        }
    }

    foundGateways.retainAll(potentialGateways); // just incase we get back some unsolicited responses
    return new HashSet<>(foundGateways);
}

From source file:com.offbynull.portmapper.natpmp.NatPmpDiscovery.java

private static Map<InetAddress, InetAddress> discoverLocalAddressesToGateways(Set<InetAddress> gateways)
        throws IOException, InterruptedException {
    Set<InetAddress> localAddresses = NetworkUtils.getAllLocalIpv4Addresses();
    List<DatagramChannel> channels = new ArrayList<>();
    final Map<DatagramChannel, InetAddress> bindMap = Collections
            .synchronizedMap(new HashMap<DatagramChannel, InetAddress>());
    final Map<InetAddress, InetAddress> localAddrToGatewayAddrMap = Collections
            .synchronizedMap(new HashMap<InetAddress, InetAddress>());

    try {//from  ww  w  .  ja  va2  s  .  co m
        for (InetAddress localAddress : localAddresses) {
            DatagramChannel unicastChannel = null;
            try {
                unicastChannel = DatagramChannel.open();
                unicastChannel.configureBlocking(false);
                unicastChannel.socket().bind(new InetSocketAddress(localAddress, 0));
            } catch (IOException ioe) {
                IOUtils.closeQuietly(unicastChannel);
                throw ioe;
            }

            channels.add(unicastChannel);
            bindMap.put(unicastChannel, localAddress);
        }
    } catch (IOException ioe) {
        for (DatagramChannel channel : channels) {
            IOUtils.closeQuietly(channel);
        }
        throw ioe;
    }

    UdpCommunicator communicator = null;
    try {
        communicator = new UdpCommunicator(channels);
        communicator.startAsync().awaitRunning();
        communicator.addListener(new UdpCommunicatorListener() {

            @Override
            public void incomingPacket(InetSocketAddress sourceAddress, DatagramChannel channel,
                    ByteBuffer packet) {
                new ExternalAddressNatPmpResponse(packet); // should error out if not valid

                InetAddress localAddress = bindMap.get(channel);
                if (localAddress == null) {
                    return;
                }
                localAddrToGatewayAddrMap.put(localAddress, sourceAddress.getAddress());
            }
        });

        ByteBuffer outBuf = ByteBuffer.allocate(16);
        ExternalAddressNatPmpRequest eanpr = new ExternalAddressNatPmpRequest();
        eanpr.dump(outBuf);

        outBuf.flip();

        for (DatagramChannel channel : bindMap.keySet()) {
            for (InetAddress gateway : gateways) {
                communicator.send(channel, new InetSocketAddress(gateway, 5351), outBuf.asReadOnlyBuffer());
            }
        }

        Thread.sleep(5000L);
    } finally {
        if (communicator != null) {
            communicator.stopAsync().awaitTerminated();
        }
    }

    return new HashMap<>(localAddrToGatewayAddrMap);
}

From source file:com.offbynull.portmapper.pcp.PcpDiscovery.java

private static Map<InetAddress, InetAddress> discoverLocalAddressesToGateways(Set<InetAddress> gateways)
        throws IOException, InterruptedException {
    Set<InetAddress> localAddresses = NetworkUtils.getAllLocalIpv4Addresses();
    List<DatagramChannel> channels = new ArrayList<>();
    final Map<DatagramChannel, InetAddress> bindMap = Collections
            .synchronizedMap(new HashMap<DatagramChannel, InetAddress>());
    final Map<InetAddress, InetAddress> localAddrToGatewayAddrMap = Collections
            .synchronizedMap(new HashMap<InetAddress, InetAddress>());

    try {/*from w  ww.  j a  v  a 2  s .  c o m*/
        for (InetAddress localAddress : localAddresses) {
            DatagramChannel unicastChannel = null;
            try {
                unicastChannel = DatagramChannel.open();
                unicastChannel.configureBlocking(false);
                unicastChannel.socket().bind(new InetSocketAddress(localAddress, 0));
            } catch (IOException ioe) {
                IOUtils.closeQuietly(unicastChannel);
                throw ioe;
            }

            channels.add(unicastChannel);
            bindMap.put(unicastChannel, localAddress);
        }
    } catch (IOException ioe) {
        for (DatagramChannel channel : channels) {
            IOUtils.closeQuietly(channel);
        }
        throw ioe;
    }

    UdpCommunicator communicator = null;
    try {
        communicator = new UdpCommunicator(channels);
        communicator.startAsync().awaitRunning();
        communicator.addListener(new UdpCommunicatorListener() {

            @Override
            public void incomingPacket(InetSocketAddress sourceAddress, DatagramChannel channel,
                    ByteBuffer packet) {
                // make sure version is 2 and error isn't ADDRESS_MISMATCH and we're good to go
                if (packet.remaining() < 4
                        || packet.get(0) == 2 && packet.get(4) == PcpResultCode.ADDRESS_MISMATCH.ordinal()) {
                    return;
                }

                InetAddress localAddress = bindMap.get(channel);
                if (localAddress == null) {
                    return;
                }
                localAddrToGatewayAddrMap.put(localAddress, sourceAddress.getAddress());
            }
        });

        for (DatagramChannel channel : bindMap.keySet()) {
            for (InetAddress gateway : gateways) {
                ByteBuffer outBuf = ByteBuffer.allocate(1100);
                MapPcpRequest mpr = new MapPcpRequest(ByteBuffer.allocate(12), 0, 0, 0,
                        InetAddress.getByName("::"), 0L);
                mpr.dump(outBuf, bindMap.get(channel));
                outBuf.flip();

                communicator.send(channel, new InetSocketAddress(gateway, 5351), outBuf.asReadOnlyBuffer());
            }
        }

        Thread.sleep(5000L);
    } finally {
        if (communicator != null) {
            communicator.stopAsync().awaitTerminated();
        }
    }

    return new HashMap<>(localAddrToGatewayAddrMap);
}

From source file:gridool.util.net.PoolableSocketChannelFactory.java

private static DatagramChannel createDatagramChannel(final SocketAddress sockAddr, final boolean blocking) {
    final DatagramChannel ch;
    try {/*from  w ww  .  j av a2s.  co m*/
        ch = DatagramChannel.open();
        ch.configureBlocking(blocking);
    } catch (IOException e) {
        LOG.error("Failed to open DatagramChannel.", e);
        throw new IllegalStateException(e);
    }
    try {
        ch.socket().setBroadcast(false);
    } catch (SocketException e) {
        LOG.error("Failed to configure socket.", e);
        throw new IllegalStateException(e);
    }
    try {
        ch.connect(sockAddr);
    } catch (IOException e) {
        LOG.error("Failed to connect socket: " + sockAddr, e);
        throw new IllegalStateException(e);
    }
    return ch;
}