Java Code Examples for java.net.DatagramSocket#send()

public static void main(String[] args) {
    try {

        DatagramSocket socket = new DatagramSocket(65001);
        byte[] buff = new byte[1024];
        DatagramPacket packet = new DatagramPacket(buff, buff.length);
        // 接收客户端发送的内容，封装到DatagramPacket中
        socket.receive(packet);

        byte[] data = packet.getData();
        // 将字节流转为字符串（输出）
        String content = new String(data, 0, packet.getLength());
        System.out.println(content);
        // 将字符串转为字节流（回写给客户端）
        byte[] bytes = String.valueOf(content.length()).getBytes();

        DatagramPacket packetToClient = new DatagramPacket(bytes, bytes.length, packet.getAddress(), packet.getPort());

        socket.send(packetToClient);

    } catch (IOException e) {
        e.printStackTrace();
    }

}
 

public static PortBean.PortNetBean scanAddress(InetAddress ia, int portNo, int timeoutMillis) {
    PortBean.PortNetBean portNetBean = new PortBean.PortNetBean();
    Long time = System.currentTimeMillis();
    try {
        byte[] bytes = new byte[128];
        DatagramPacket dp = new DatagramPacket(bytes, bytes.length);

        DatagramSocket ds = new DatagramSocket();
        ds.setSoTimeout(timeoutMillis);
        ds.connect(ia, portNo);
        ds.send(dp);
        ds.isConnected();
        ds.receive(dp);
        ds.close();
        portNetBean.setConnected(true);
    } catch (SocketTimeoutException e) {

    } catch (Exception ignore) {

    }
    portNetBean.setPort(portNo);
    portNetBean.setDelay(System.currentTimeMillis() - time);
    return portNetBean;
}
 

/**
 * Sends this packet to the EventServer
 * @param adr Address of the EventServer
 * @param port Port of the EventServer
 * @throws IOException
 */
public void send(InetAddress adr, int port) throws IOException
{
	int maxseq = getNumPackets();
	DatagramSocket s = new DatagramSocket();
	// For each Packet in Sequence...
	for(int seq=1;seq<=maxseq;seq++)
	{
		// Get Message and send them...
		byte[] pack = getUDPMessage(seq);
		DatagramPacket p = new DatagramPacket(pack, pack.length);
		p.setAddress(adr);
		p.setPort(port);
		s.send(p);
	}
}
 

public void shutdown() {
  try {
    DatagramSocket clientSocket = new DatagramSocket();
    String shutdownSignal = "shutdown";
    byte[] sendBuffer = shutdownSignal.getBytes();
    DatagramPacket packet =
        new DatagramPacket(sendBuffer, sendBuffer.length, new InetSocketAddress("localhost",
            port));
    clientSocket.send(packet);
  } catch (IOException e) {
    logger.error(e.getMessage(), e);
  }
  stop = true;
  if (thread != null) {
    thread.interrupt();
  }
}
 

@Override
public InputStream getStream( String request ) throws Exception
{
	byte[] path = getAbsolute( request ).getBytes();

	DatagramPacket outgoing = new DatagramPacket( path, path.length );
	DatagramPacket incoming = new DatagramPacket( new byte[packetSize], packetSize );

	DatagramSocket s = new DatagramSocket();
	s.connect( address );
	s.send( outgoing );
	s.receive( incoming );

	return new DatagramInputStream( incoming.getData(), 0, incoming.getLength(), s );
}
 

/**
 *  Starts a new thread to reply to broadcast discovery requests from nodes.
 *
 * @throws SocketException if cannot bind UDP socket
 * @throws UnknownHostException if cannot bind to 0.0.0.0
 */
public void start() throws SocketException, UnknownHostException {
    broadcastSocket = new DatagramSocket(port, InetAddress.getByName("0.0.0.0"));
    broadcastSocket.setBroadcast(true);

    discoveryThread = new Thread(new Runnable() {
        @Override
        public void run() {
            for (;;) {
                try {
                    DatagramPacket nodePacket = new DatagramPacket(new byte[0], 0);
                    broadcastSocket.receive(nodePacket);

                    byte[] urlAsBytes = url.getBytes(BroadcastDiscoveryClient.BROADCAST_ENCODING);
                    DatagramPacket replyPacket = new DatagramPacket(urlAsBytes,
                                                                    urlAsBytes.length,
                                                                    nodePacket.getAddress(),
                                                                    nodePacket.getPort());
                    broadcastSocket.send(replyPacket);
                } catch (SocketException e) {
                    if (needsToStop) {
                        return;
                    } else {
                        logger.warn("Could not broadcast URL to node", e);
                    }
                } catch (Exception e) {
                    logger.warn("Could not broadcast URL to node", e);
                }
            }
        }
    }, "BroadcastDiscovery");
    discoveryThread.start();
}
 

@Override
public void run() {
    try {
        int port = NetworkUtil.BASE_PORT;
        boolean portAvailable = false;
        do {
            if (NetworkUtil.available(port))
                portAvailable = true;
            else
                port--;
        } while (!portAvailable);

        socket = new DatagramSocket(port, InetAddress.getByName("0.0.0.0"));
        socket.setBroadcast(true);

        while (true) {
            // Receive broadcast packet
            Log.d("USER", "Waiting for packet...");
            byte[] buffer = new byte[15000];
            DatagramPacket receivePacket = new DatagramPacket(buffer, buffer.length);
            socket.receive(receivePacket);
            Log.d("USER", "Received packet from: " + receivePacket.getAddress().getHostAddress());

            // Send reply
            byte[] replyPacket = SerializationUtil.serialize(reply);
            socket.send(new DatagramPacket(replyPacket, replyPacket.length, receivePacket.getAddress(), receivePacket.getPort()));
        }
    } catch (IOException e) {
        e.printStackTrace();
    }
}
 

public static void main(String[] args) throws Exception { // 所有异常抛出
    String str = "hello World!!!";
    DatagramSocket ds = new DatagramSocket(3000); // 服务端在3000端口上等待服务器发送信息
    DatagramPacket dp =
        new DatagramPacket(str.getBytes(), str.length(), InetAddress.getByName("localhost"), 9000); // 所有的信息使用buf保存
    System.out.println("发送信息。");
    ds.send(dp); // 发送信息出去
    ds.close();
}
 

/**
 * This function sends an array of bytes to the WiFi box. The bytes should
 * be a valid command, i.e. the array's length should be three.
 * 
 * @param messages
 *            is an array of message codes to send
 * @throws IllegalArgumentException
 *             if the length of the array is not 3
 * @throws IOException
 *             if the message could not be sent
 */
private void sendMessage(byte[] messages) throws IOException {
	// check arguments
	if (messages.length != 3) {
		throw new IllegalArgumentException(
				"The message to send should consist of exactly 3 bytes.");
	}

	// notify listeners
	notifyLightListeners(messages);

	// send message
	DatagramSocket socket = new DatagramSocket();
	DatagramPacket packet = new DatagramPacket(messages, messages.length,
			address, port);
	socket.send(packet);
	socket.close();

	// adjust currently active group of lights
	switch (messages[0]) {
	case COMMAND_GROUP_1_ON:
	case COMMAND_GROUP_1_OFF:
		activeGroup = 1;
		break;
	case COMMAND_GROUP_2_ON:
	case COMMAND_GROUP_2_OFF:
		activeGroup = 2;
		break;
	case COMMAND_GROUP_3_ON:
	case COMMAND_GROUP_3_OFF:
		activeGroup = 3;
		break;
	case COMMAND_GROUP_4_ON:
	case COMMAND_GROUP_4_OFF:
		activeGroup = 4;
		break;
	}
}
 

public void run() throws IOException {
  InetAddress IPAddress = InetAddress.getByName(host);
  byte[] sendData = request.getBytes();
  byte[] receiveData = new byte[65535];
  // Use the provided socket if there is one, else just make a new one.
  DatagramSocket socket = this.clientSocket == null ?
      new DatagramSocket() : this.clientSocket;

  try {
    DatagramPacket sendPacket = new DatagramPacket(sendData, sendData.length,
        IPAddress, port);
    socket.send(sendPacket);
    socket.setSoTimeout(500);
    DatagramPacket receivePacket = new DatagramPacket(receiveData,
        receiveData.length);
    socket.receive(receivePacket);

    // Check reply status
    XDR xdr = new XDR(Arrays.copyOfRange(receiveData, 0,
        receivePacket.getLength()));
    RpcReply reply = RpcReply.read(xdr);
    if (reply.getState() != RpcReply.ReplyState.MSG_ACCEPTED) {
      throw new IOException("Request failed: " + reply.getState());
    }
  } finally {
    // If the client socket was passed in to this UDP client, it's on the
    // caller of this UDP client to close that socket.
    if (this.clientSocket == null) {
      socket.close();
    }
  }
}
 

private void broadcast(int udpPort, DatagramSocket socket, byte[] data) throws IOException {
	for (NetworkInterface iface : Collections.list(NetworkInterface.getNetworkInterfaces())) {
		for (InetAddress address : Collections.list(iface.getInetAddresses())) {
			if (!address.isSiteLocalAddress())
				continue;
			// Java 1.5 doesn't support getting the subnet mask, so try the two most common.
			byte[] ip = address.getAddress();
			ip[3] = -1; // 255.255.255.0
			socket.send(new DatagramPacket(data, data.length, InetAddress.getByAddress(ip), udpPort));
			ip[2] = -1; // 255.255.0.0
			socket.send(new DatagramPacket(data, data.length, InetAddress.getByAddress(ip), udpPort));
		}
	}
}
 

public void run() throws IOException {
  InetAddress IPAddress = InetAddress.getByName(host);
  byte[] sendData = request.getBytes();
  byte[] receiveData = new byte[65535];
  // Use the provided socket if there is one, else just make a new one.
  DatagramSocket socket = this.clientSocket == null ?
      new DatagramSocket() : this.clientSocket;

  try {
    DatagramPacket sendPacket = new DatagramPacket(sendData, sendData.length,
        IPAddress, port);
    socket.send(sendPacket);
    socket.setSoTimeout(500);
    DatagramPacket receivePacket = new DatagramPacket(receiveData,
        receiveData.length);
    socket.receive(receivePacket);

    // Check reply status
    XDR xdr = new XDR(Arrays.copyOfRange(receiveData, 0,
        receivePacket.getLength()));
    RpcReply reply = RpcReply.read(xdr);
    if (reply.getState() != RpcReply.ReplyState.MSG_ACCEPTED) {
      throw new IOException("Request failed: " + reply.getState());
    }
  } finally {
    // If the client socket was passed in to this UDP client, it's on the
    // caller of this UDP client to close that socket.
    if (this.clientSocket == null) {
      socket.close();
    }
  }
}
 

@Test(timeout = 1000)
public void testRegistration() throws IOException, InterruptedException {
  XDR req = new XDR();
  RpcCall.getInstance(++xid, RpcProgramPortmap.PROGRAM,
      RpcProgramPortmap.VERSION,
      RpcProgramPortmap.PMAPPROC_SET,
      new CredentialsNone(), new VerifierNone()).write(req);

  PortmapMapping sent = new PortmapMapping(90000, 1,
      PortmapMapping.TRANSPORT_TCP, 1234);
  sent.serialize(req);

  byte[] reqBuf = req.getBytes();
  DatagramSocket s = new DatagramSocket();
  DatagramPacket p = new DatagramPacket(reqBuf, reqBuf.length,
      pm.getUdpServerLoAddress());
  try {
    s.send(p);
  } finally {
    s.close();
  }

  // Give the server a chance to process the request
  Thread.sleep(100);
  boolean found = false;
  @SuppressWarnings("unchecked")
  Map<String, PortmapMapping> map = (Map<String, PortmapMapping>) Whitebox
      .getInternalState(pm.getHandler(), "map");

  for (PortmapMapping m : map.values()) {
    if (m.getPort() == sent.getPort()
        && PortmapMapping.key(m).equals(PortmapMapping.key(sent))) {
      found = true;
      break;
    }
  }
  Assert.assertTrue("Registration failed", found);
}
 

private void broadcastToDefaultInterface(DatagramSocket broadcastSocket) {
    try {
        DatagramPacket sendPacket = new DatagramPacket(new byte[0],
                                                       0,
                                                       InetAddress.getByName("255.255.255.255"),
                                                       port);
        broadcastSocket.send(sendPacket);
    } catch (Exception e) {
        logger.warn("Could not broadcast to default interface", e);
    }
}
 

public static void sendTestUDP(int size) throws IOException {
    byte[] buffer = new byte[size];
    InetAddress address = InetAddress.getByName(TESTIP);
    DatagramPacket packet = new DatagramPacket(buffer, buffer.length, address, TESTPORT);
    DatagramSocket socket = new DatagramSocket();
    socket.send(packet);
}
 

private void test3()
    throws UtilityException, SocketException, UnknownHostException, IOException,
        MessageAttributeParsingException, MessageAttributeException,
        MessageHeaderParsingException {
  int timeSinceFirstTransmission = 0;
  int timeout = timeoutInitValue;
  do {
    try {
      // Test 3 including response
      DatagramSocket sendSocket = new DatagramSocket(new InetSocketAddress(iaddress, 0));
      sendSocket.connect(InetAddress.getByName(stunServer), port);
      sendSocket.setSoTimeout(timeout);

      MessageHeader sendMH = new MessageHeader(MessageHeader.MessageHeaderType.BindingRequest);
      sendMH.generateTransactionID();

      ChangeRequest changeRequest = new ChangeRequest();
      changeRequest.setChangePort();
      sendMH.addMessageAttribute(changeRequest);

      byte[] data = sendMH.getBytes();
      DatagramPacket send = new DatagramPacket(data, data.length);
      sendSocket.send(send);
      LOGGER.debug("Test 3: Binding Request sent.");

      int localPort = sendSocket.getLocalPort();
      InetAddress localAddress = sendSocket.getLocalAddress();

      sendSocket.close();

      DatagramSocket receiveSocket = new DatagramSocket(localPort, localAddress);
      receiveSocket.connect(InetAddress.getByName(stunServer), ca.getPort());
      receiveSocket.setSoTimeout(timeout);

      MessageHeader receiveMH = new MessageHeader();
      while (!receiveMH.equalTransactionID(sendMH)) {
        DatagramPacket receive = new DatagramPacket(new byte[200], 200);
        receiveSocket.receive(receive);
        receiveMH = MessageHeader.parseHeader(receive.getData());
        receiveMH.parseAttributes(receive.getData());
      }
      ErrorCode ec =
          (ErrorCode)
              receiveMH.getMessageAttribute(MessageAttribute.MessageAttributeType.ErrorCode);
      if (ec != null) {
        di.setError(ec.getResponseCode(), ec.getReason());
        LOGGER.debug("Message header contains an Errorcode message attribute.");
        return;
      }
      if (nodeNatted) {
        di.setRestrictedCone();
        LOGGER.debug("Node is behind a restricted NAT.");
        return;
      }
    } catch (SocketTimeoutException ste) {
      if (timeSinceFirstTransmission < 7900) {
        LOGGER.debug("Test 3: Socket timeout while receiving the response.");
        timeSinceFirstTransmission += timeout;
        int timeoutAddValue = timeSinceFirstTransmission * 2;
        if (timeoutAddValue > 1600) {
          timeoutAddValue = 1600;
        }
        timeout = timeoutAddValue;
      } else {
        LOGGER.debug(
            "Test 3: Socket timeout while receiving the response. Maximum retry limit exceed. Give up.");
        di.setPortRestrictedCone();
        LOGGER.debug("Node is behind a port restricted NAT.");
        return;
      }
    }
  } while (true);
}
 

private void sendResponse(DatagramSocket sock, SocketAddress sender, byte[] buf) throws IOException {
    DatagramPacket p=new DatagramPacket(buf, 0, buf.length, sender);
    sock.send(p);
}
 

/**
 * Sends a bunch of UDP packets of the size indicated and wait for the response.
 * 
 * Counts how long it takes for all the packets to return. PAckets are currently not labelled: the
 * total time is the time for the first packet to leave until the last packet arrives. AFter 7000
 * ms it is assumed packets are lost and the socket times out. In that case, the number of packets
 * lost is recorded.
 * 
 * @param serverAddr server to which to send the packets
 * @param size size of the packets
 * @param num number of packets to send
 * @param packetSize size of the packets sent
 * @param port port to send the packets to
 * @return first value: the amount of time to send all packets and get a response. second value:
 *         number of packets lost, on a timeout.
 * @throws IOException
 */
public static long[] sendMultiPackets(InetAddress serverAddr, int size, int num, int packetSize,
    int port) throws IOException {

  long startTime = 0;
  long endTime = 0;
  byte[] buf = new byte[size];
  byte[] rcvBuf = new byte[packetSize];
  long[] retval = {-1, -1};
  long numLost = 0;
  int i = 0;
  long dataConsumedThisTask = 0;

  DatagramSocket socket = new DatagramSocket();
  DatagramPacket packetRcv = new DatagramPacket(rcvBuf, rcvBuf.length);
  DatagramPacket packet = new DatagramPacket(buf, buf.length, serverAddr, port);
  
  // number * (packet sent + packet received)
  dataConsumedThisTask += num * (size + packetSize);

  try {
    socket.setSoTimeout(7000);
    startTime = System.currentTimeMillis();
    Logger.d("Sending packet, waiting for response ");
    for (i = 0; i < num; i++) {
      socket.send(packet);
    }
    for (i = 0; i < num; i++) {
      socket.receive(packetRcv);
      if (i == 0) {

        endTime = System.currentTimeMillis();
      }
    }
  } catch (SocketTimeoutException e) {
    Logger.d("Timed out");
    numLost += (num - i);
    socket.close();
  }
  Logger.d("Sending complete: " + endTime);

  retval[0] = endTime - startTime;
  retval[1] = numLost;

  incrementData(dataConsumedThisTask);
  return retval;
}
 

protected void run(final DatagramSocket socket, final List<String> messages, final int expectedQueueSize, final int expectedTransferred)
        throws IOException, InterruptedException {

    try {
        // schedule to start listening on a random port
        final ProcessSessionFactory processSessionFactory = runner.getProcessSessionFactory();
        final ProcessContext context = runner.getProcessContext();
        proc.onScheduled(context);
        Thread.sleep(100);

        // get the real port the dispatcher is listening on
        final int destPort = proc.getDispatcherPort();
        final InetSocketAddress destination = new InetSocketAddress("localhost", destPort);

        // send the messages to the port the processors is listening on
        for (final String message : messages) {
            final byte[] buffer = message.getBytes(StandardCharsets.UTF_8);
            final DatagramPacket packet = new DatagramPacket(buffer, buffer.length, destination);
            socket.send(packet);
            Thread.sleep(10);
        }

        long responseTimeout = 10000;

        // this first loop waits until the internal queue of the processor has the expected
        // number of messages ready before proceeding, we want to guarantee they are all there
        // before onTrigger gets a chance to run
        long startTimeQueueSizeCheck = System.currentTimeMillis();
        while (proc.getQueueSize() < expectedQueueSize
                && (System.currentTimeMillis() - startTimeQueueSizeCheck < responseTimeout)) {
            Thread.sleep(100);
        }

        // want to fail here if the queue size isn't what we expect
        Assert.assertEquals(expectedQueueSize, proc.getQueueSize());

        // call onTrigger until we processed all the messages, or a certain amount of time passes
        int numTransferred = 0;
        long startTime = System.currentTimeMillis();
        while (numTransferred < expectedTransferred  && (System.currentTimeMillis() - startTime < responseTimeout)) {
            proc.onTrigger(context, processSessionFactory);
            numTransferred = runner.getFlowFilesForRelationship(ListenUDP.REL_SUCCESS).size();
            Thread.sleep(100);
        }

        // should have transferred the expected events
        runner.assertTransferCount(ListenUDP.REL_SUCCESS, expectedTransferred);
    } finally {
        // unschedule to close connections
        proc.onUnscheduled();
        IOUtils.closeQuietly(socket);
    }
}
 

public void discover() throws Exception {

    InetAddress server = InetAddress.getByName("127.0.0.1");

    Node from = Node.instanceOf("127.0.0.1:10002");
    Node peer1 = Node.instanceOf("127.0.0.1:10003");
    Node peer2 = Node.instanceOf("127.0.0.1:10004");

    Assert.assertTrue(!nodeManager.hasNodeHandler(peer1));
    Assert.assertTrue(!nodeManager.hasNodeHandler(peer2));
    Assert.assertTrue(nodeManager.getTable().getAllNodes().isEmpty());

    PingMessage pingMessage = new PingMessage(from, nodeManager.getPublicHomeNode());
    DatagramPacket pingPacket = new DatagramPacket(pingMessage.getSendData(),
        pingMessage.getSendData().length, server, port);

    FindNodeMessage findNodeMessage = new FindNodeMessage(from, Node.getNodeId());
    DatagramPacket findNodePacket = new DatagramPacket(findNodeMessage.getSendData(),
        findNodeMessage.getSendData().length, server, port);

    DatagramSocket socket = new DatagramSocket();

    // send ping msg
    socket.send(pingPacket);
    byte[] data = new byte[1024];
    DatagramPacket packet = new DatagramPacket(data, data.length);

    boolean pingFlag = false;
    boolean pongFlag = false;
    boolean findNodeFlag = false;
    boolean neighborsFlag = false;
    while (true) {
      socket.receive(packet);
      byte[] bytes = Arrays.copyOfRange(data, 0, packet.getLength());
      Message msg = Message.parse(bytes);
      Assert.assertTrue(
          Arrays.equals(msg.getFrom().getId(), nodeManager.getPublicHomeNode().getId()));
      if (!pingFlag) {
        pingFlag = true;
        Assert.assertTrue(msg instanceof PingMessage);
        Assert.assertTrue(Arrays.equals(((PingMessage) msg).getTo().getId(), from.getId()));
        PongMessage pongMessage = new PongMessage(from, msg.getTimestamp());
        DatagramPacket pongPacket = new DatagramPacket(pongMessage.getSendData(),
            pongMessage.getSendData().length, server, port);
        socket.send(pongPacket);
      } else if (!pongFlag) {
        pongFlag = true;
        Assert.assertTrue(msg instanceof PongMessage);
      } else if (!findNodeFlag) {
        findNodeFlag = true;
        Assert.assertTrue(msg instanceof FindNodeMessage);
        List<Node> peers = Lists.newArrayList(peer1, peer2);
        NeighborsMessage neighborsMessage = new NeighborsMessage(from, peers, msg.getTimestamp());
        DatagramPacket neighborsPacket = new DatagramPacket(neighborsMessage.getSendData(),
            neighborsMessage.getSendData().length, server, port);
        socket.send(neighborsPacket);
        socket.send(findNodePacket);
      } else if (!neighborsFlag) {
        Assert.assertTrue(msg instanceof NeighborsMessage);
        break;
      }
    }

    Assert.assertTrue(nodeManager.hasNodeHandler(peer1));

    Assert.assertTrue(nodeManager.hasNodeHandler(peer2));

    Assert.assertTrue(nodeManager.getTable().getAllNodes().size() == 1);

    socket.close();

  }