Examples with DatagramPacket java.net.DatagramPacket used on opensource projects

Example 16 with DatagramPacket

use of java.net.DatagramPacket in project malmo by Microsoft.

the class UDPSocketHelper method sendUDPString.

/** Send string over UDP to the specified address via the specified port.
     * @param message string to be sent over UDP
     * @param address address to send the message to
     * @param port port number to use
     * @return true if message was successfully sent
     */
public static boolean sendUDPString(String message, InetAddress address, int port) {
    DatagramPacket packet = null;
    boolean succeeded = true;
    packet = new DatagramPacket(message.getBytes(), message.length(), address, port);
    DatagramSocket socket = null;
    try {
        socket = new DatagramSocket();
    } catch (SocketException e1) {
        System.out.println("Error creating UDP socket");
        succeeded = false;
    }
    if (socket != null) {
        try {
            socket.send(packet);
        } catch (IOException e) {
            System.out.println("Error sending UDP packet");
            succeeded = false;
        }
        socket.close();
    }
    return succeeded;
}

Example 17 with DatagramPacket

use of java.net.DatagramPacket in project actor-platform by actorapp.

the class SntpClient method requestTime.

/**
     * Sends an SNTP request to the given host and processes the response.
     *
     * @param host    host name of the server.
     * @param timeout network timeout in milliseconds.
     * @return true if the transaction was successful.
     */
public boolean requestTime(String host, int timeout) {
    DatagramSocket socket = null;
    try {
        socket = new DatagramSocket();
        socket.setSoTimeout(timeout);
        InetAddress address = InetAddress.getByName(host);
        byte[] buffer = new byte[NTP_PACKET_SIZE];
        DatagramPacket request = new DatagramPacket(buffer, buffer.length, address, NTP_PORT);
        // set mode = 3 (client) and version = 3
        // mode is in low 3 bits of first byte
        // version is in bits 3-5 of first byte
        buffer[0] = NTP_MODE_CLIENT | (NTP_VERSION << 3);
        // get current time and write it to the request packet
        long requestTime = System.currentTimeMillis();
        long requestTicks = SystemClock.elapsedRealtime();
        writeTimeStamp(buffer, TRANSMIT_TIME_OFFSET, requestTime);
        socket.send(request);
        // read the response
        DatagramPacket response = new DatagramPacket(buffer, buffer.length);
        socket.receive(response);
        long responseTicks = SystemClock.elapsedRealtime();
        long responseTime = requestTime + (responseTicks - requestTicks);
        // extract the results
        long originateTime = readTimeStamp(buffer, ORIGINATE_TIME_OFFSET);
        long receiveTime = readTimeStamp(buffer, RECEIVE_TIME_OFFSET);
        long transmitTime = readTimeStamp(buffer, TRANSMIT_TIME_OFFSET);
        long roundTripTime = responseTicks - requestTicks - (transmitTime - receiveTime);
        // receiveTime = originateTime + transit + skew
        // responseTime = transmitTime + transit - skew
        // clockOffset = ((receiveTime - originateTime) + (transmitTime - responseTime))/2
        //             = ((originateTime + transit + skew - originateTime) +
        //                (transmitTime - (transmitTime + transit - skew)))/2
        //             = ((transit + skew) + (transmitTime - transmitTime - transit + skew))/2
        //             = (transit + skew - transit + skew)/2
        //             = (2 * skew)/2 = skew
        mClockOffset = ((receiveTime - originateTime) + (transmitTime - responseTime)) / 2;
        // if (false) Log.d(TAG, "round trip: " + roundTripTime + " ms");
        // if (false) Log.d(TAG, "clock offset: " + clockOffset + " ms");
        // save our results - use the times on this side of the network latency
        // (response rather than request time)
        mNtpTime = responseTime + mClockOffset;
        mNtpTimeReference = responseTicks;
        mRoundTripTime = roundTripTime;
    } catch (Exception e) {
        return false;
    } finally {
        if (socket != null) {
            socket.close();
        }
    }
    return true;
}

Example 18 with DatagramPacket

use of java.net.DatagramPacket in project jmonkeyengine by jMonkeyEngine.

the class UdpEndpoint method send.

public void send(ByteBuffer data) {
    if (!isConnected()) {
        throw new KernelException("Endpoint is not connected:" + this);
    }
    try {
        DatagramPacket p = new DatagramPacket(data.array(), data.position(), data.remaining(), address);
        // Just queue it up for the kernel threads to write
        // out
        kernel.enqueueWrite(this, p);
    //socket.send(p);
    } catch (Exception e) {
        if (e instanceof SocketException) {
            throw new KernelException("Error sending datagram to:" + address, e);
        } else if (e instanceof RuntimeException) {
            throw (RuntimeException) e;
        } else {
            throw new RuntimeException(e);
        }
    }
}

Example 19 with DatagramPacket

use of java.net.DatagramPacket in project Smack by igniterealtime.

the class TcpUdpBridgeClient method startBridge.

public void startBridge() {
    final Thread process = new Thread(new Runnable() {

        @Override
        public void run() {
            try {
                OutputStream out = localTcpSocket.getOutputStream();
                while (true) {
                    byte[] b = new byte[500];
                    DatagramPacket p = new DatagramPacket(b, 500);
                    localUdpSocket.receive(p);
                    if (p.getLength() == 0)
                        continue;
                    LOGGER.fine("UDP Client Received and Sending to TCP Server:" + new String(p.getData(), 0, p.getLength(), "UTF-8"));
                    out.write(p.getData(), 0, p.getLength());
                    out.flush();
                    LOGGER.fine("Client Flush");
                }
            } catch (IOException e) {
                LOGGER.log(Level.WARNING, "exception", e);
            }
        }
    });
    new Thread(new Runnable() {

        @Override
        public void run() {
            try {
                InputStream in = localTcpSocket.getInputStream();
                InetAddress remoteHost = InetAddress.getByName(remoteUdpHost);
                process.start();
                while (true) {
                    byte[] b = new byte[500];
                    int s = in.read(b);
                    //if (s == -1) continue;
                    LOGGER.fine("TCP Client:" + new String(b, 0, s, "UTF-8"));
                    DatagramPacket udpPacket = new DatagramPacket(b, s);
                    udpPacket.setAddress(remoteHost);
                    udpPacket.setPort(remoteUdpPort);
                    localUdpSocket.send(udpPacket);
                }
            } catch (IOException e) {
                LOGGER.log(Level.WARNING, "exception", e);
            }
        }
    }).start();
}

Example 20 with DatagramPacket

use of java.net.DatagramPacket in project Smack by igniterealtime.

the class TcpUdpBridgeServer method startBridge.

public void startBridge() {
    final Thread process = new Thread(new Runnable() {

        @Override
        public void run() {
            try {
                OutputStream out = localTcpSocket.getOutputStream();
                while (true) {
                    byte[] b = new byte[500];
                    DatagramPacket p = new DatagramPacket(b, 500);
                    localUdpSocket.receive(p);
                    if (p.getLength() == 0)
                        continue;
                    LOGGER.fine("UDP Server Received and Sending to TCP Client:" + new String(p.getData(), 0, p.getLength(), "UTF-8"));
                    out.write(p.getData(), 0, p.getLength());
                    out.flush();
                    LOGGER.fine("Server Flush");
                }
            } catch (IOException e) {
                LOGGER.log(Level.WARNING, "exception", e);
            }
        }
    });
    new Thread(new Runnable() {

        @Override
        public void run() {
            try {
                localTcpSocket = serverTcpSocket.accept();
                process.start();
                InputStream in = localTcpSocket.getInputStream();
                InetAddress remoteHost = InetAddress.getByName(remoteUdpHost);
                while (true) {
                    byte[] b = new byte[500];
                    int s = in.read(b);
                    //if (s == -1) continue;
                    LOGGER.fine("TCP Server:" + new String(b, 0, s, "UTF-8"));
                    DatagramPacket udpPacket = new DatagramPacket(b, s);
                    udpPacket.setAddress(remoteHost);
                    udpPacket.setPort(remoteUdpPort);
                    localUdpSocket.send(udpPacket);
                }
            } catch (IOException e) {
                LOGGER.log(Level.WARNING, "exception", e);
            }
        }
    }).start();
}