public static void main(String[] args) throws IOException, InterruptedException {
boolean running = true;
// udp protocol over a socket.
DatagramSocket socket = new DatagramSocket();
while (running) {
BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
String line = br.readLine();
String[] inputs = line.split(" ");
if (inputs.length < 2) {
System.out.println("Usage: username command id");
socket.close();
return;
}
byte[] byteArr = (inputs[0] + " " + inputs[1] + " " + inputs[2]).getBytes();
// send request
byte[] buf = new byte[256];
InetAddress address = InetAddress.getByName("localhost");
DatagramPacket packet = new DatagramPacket(byteArr, byteArr.length, address, 4445);
socket.send(packet);
// get response
packet = new DatagramPacket(buf, buf.length);
socket.receive(packet);
// display response
String received = new String(packet.getData(), 0, packet.getLength());
System.out.println("From server: " + received);
}
// socket.close();
}
public void run() {
if (ServerSocket == null) return;
while (true) {
try {
InetAddress address;
int port;
DatagramPacket packet;
byte[] data = new byte[1460];
packet = new DatagramPacket(data, data.length);
ServerSocket.receive(packet);
//
//
address = packet.getAddress();
port = packet.getPort();
System.out.println("get the Client port is: " + port);
System.out.println("get the data length is: " + data.length);
FileWriter fw = new FileWriter("Fortunes.txt");
PrintWriter out = new PrintWriter(fw);
for (int i = 0; i < data.length; i++) {
out.print(data[i] + " ");
}
out.close();
System.out.println("Data has been writen to destination!");
packet = new DatagramPacket(data, data.length, address, port);
ServerSocket.send(packet);
System.out.println("Respond has been made!");
} catch (Exception e) {
System.err.println("Exception: " + e);
e.printStackTrace();
}
}
}
public void run() {
try {
while (running) {
byte[] sendClientData = new byte[512];
byte[] sendServerData = new byte[512];
byte[] receiveClientData = new byte[512];
byte[] receiveServerData = new byte[512];
DatagramPacket receiveClientPacket = receivePacket(receiveClientData, receiveSocket);
receiveClientPacket.getLength();
// find port used by client
int clientPort = receiveClientPacket.getPort();
DatagramSocket hostSocket = new DatagramSocket();
sendServerData = receiveClientPacket.getData();
sendPacket(sendServerData, serverIPAddress, ServerPort, hostSocket);
DatagramPacket receiveServerPacket = receivePacket(receiveServerData, hostSocket);
if (receiveServerPacket.getData()[0] == 1) {
running = false;
}
sendClientData = receiveServerPacket.getData();
sendPacket(sendClientData, clientIPAddress, clientPort, hostSocket);
hostSocket.close();
}
receiveSocket.close();
} catch (Exception e) {
e.printStackTrace();
}
}
public static void main(String[] args) {
int port = 5555;
DatagramSocket socket;
socket = null;
try {
socket = new DatagramSocket(port);
socket.setBroadcast(true);
socket.connect(InetAddress.getByName("255.255.255.255"), 5555);
} catch (Exception e) {
System.err.println("Connection failed. " + e.getMessage());
}
while (true) {
String message = "hey";
byte[] buf = message.getBytes();
DatagramPacket packet = new DatagramPacket(buf, buf.length);
try {
socket.send(packet);
} catch (Exception e) {
System.err.println("Sending failed. " + e.getMessage());
}
}
}
public void run() {
while (moreQuotes) {
try {
byte[] buf = new byte[256];
// receive request
DatagramPacket packet = new DatagramPacket(buf, buf.length);
socket.receive(packet); // containing IP ecc.
// figure out response
String dString = null;
if (in == null) dString = new Date().toString();
else dString = getNextQuote();
buf = dString.getBytes();
// send the response to the client at "address" and "port"
InetAddress address = packet.getAddress();
int port = packet.getPort();
packet = new DatagramPacket(buf, buf.length, address, port);
socket.send(packet);
} catch (IOException e) {
e.printStackTrace();
moreQuotes = false;
}
}
socket.close();
}
void setBufferSizes() {
if (sock != null) {
try {
sock.setSendBufferSize(ucast_send_buf_size);
} catch (Throwable ex) {
Trace.warn("UDP.setBufferSizes()", "failed setting ucast_send_buf_size in sock: " + ex);
}
try {
sock.setReceiveBufferSize(ucast_recv_buf_size);
} catch (Throwable ex) {
Trace.warn("UDP.setBufferSizes()", "failed setting ucast_recv_buf_size in sock: " + ex);
}
}
if (mcast_sock != null) {
try {
mcast_sock.setSendBufferSize(mcast_send_buf_size);
} catch (Throwable ex) {
Trace.warn(
"UDP.setBufferSizes()", "failed setting mcast_send_buf_size in mcast_sock: " + ex);
}
try {
mcast_sock.setReceiveBufferSize(mcast_recv_buf_size);
} catch (Throwable ex) {
Trace.warn(
"UDP.setBufferSizes()", "failed setting mcast_recv_buf_size in mcast_sock: " + ex);
}
}
}
public static void main(String args[]) throws Exception {
// Making a text file
String filename =
"C:\\Users\\S.S. Mehta\\Desktop\\Codes\\ComputerNetworks\\CN_project\\CN_project\\test3.txt";
makeTextFile(filename);
// Reading the file and puttin it in buffer
BufferedReader in = new BufferedReader(new FileReader(filename));
char[] c1 = new char[PACKET_SIZE];
c1 = readData(in);
displayPacket(c1);
// Step3 - making a socket , makeing a packet with inet address and sending it
byte[] buffer = new byte[PACKET_SIZE];
DatagramSocket skt = new DatagramSocket(PORT_NUMBER);
DatagramPacket request = new DatagramPacket(buffer, buffer.length);
// stop till you receive
wait(skt, request);
System.out.println("On server side \nrequest received from Slient");
// making a packet with an inet address -
InetAddress host = InetAddress.getByName("localhost");
DatagramPacket reply = makePacket(c1, host);
// Sending reply packet
System.out.println("Sending reply packet to client");
Thread.sleep(5000);
skt.send(reply);
// closing the socket
skt.close();
}
public static void main(String args[]) {
DatagramSocket skt = null;
try {
skt = new DatagramSocket(6789);
byte[] buffer = new byte[1000];
while (true) {
DatagramPacket request = new DatagramPacket(buffer, buffer.length);
skt.receive(request);
System.out.println("Data received from client");
System.out.println(new String(request.getData()));
Thread.sleep(15000);
String[] arrayMsg = (new String(request.getData())).split(" ");
System.out.println(arrayMsg[0] + "server processed");
byte[] sendMsg = (arrayMsg[0] + "server processed").getBytes();
DatagramPacket reply =
new DatagramPacket(sendMsg, sendMsg.length, request.getAddress(), request.getPort());
System.out.println("sending data from server to client");
Thread.sleep(15000);
;
skt.send(reply);
}
} catch (Exception e) {
}
}
/**
* Tries to obtain a mapped/public address for the specified port (possibly by executing a STUN
* query).
*
* @param dst the destination that we'd like to use this address with.
* @param port the port whose mapping we are interested in.
* @return a public address corresponding to the specified port or null if all attempts to
* retrieve such an address have failed.
* @throws IOException if an error occurs while stun4j is using sockets.
* @throws BindException if the port is already in use.
*/
public InetSocketAddress getPublicAddressFor(InetAddress dst, int port)
throws IOException, BindException {
if (!useStun || (dst instanceof Inet6Address)) {
logger.debug(
"Stun is disabled for destination "
+ dst
+ ", skipping mapped address recovery (useStun="
+ useStun
+ ", IPv6@="
+ (dst instanceof Inet6Address)
+ ").");
// we'll still try to bind though so that we could notify the caller
// if the port has been taken already.
DatagramSocket bindTestSocket = new DatagramSocket(port);
bindTestSocket.close();
// if we're here then the port was free.
return new InetSocketAddress(getLocalHost(dst), port);
}
StunAddress mappedAddress = queryStunServer(port);
InetSocketAddress result = null;
if (mappedAddress != null) result = mappedAddress.getSocketAddress();
else {
// Apparently STUN failed. Let's try to temporarily disble it
// and use algorithms in getLocalHost(). ... We should probably
// eveng think about completely disabling stun, and not only
// temporarily.
// Bug report - John J. Barton - IBM
InetAddress localHost = getLocalHost(dst);
result = new InetSocketAddress(localHost, port);
}
if (logger.isDebugEnabled())
logger.debug("Returning mapping for port:" + port + " as follows: " + result);
return result;
}
public static void main(String args[]) {
DatagramSocket aSocket = null;
try {
aSocket = new DatagramSocket();
String stringMsg = "0";
String prevReply = "0";
InetAddress aHost =
InetAddress.getByName("localhost"); // recieve a message from the same computer
int serverPort = 6789; // agreed port
while (true) {
stringMsg = "" + (Integer.parseInt(stringMsg) + 1);
byte[] message = stringMsg.getBytes();
DatagramPacket request = new DatagramPacket(message, message.length, aHost, serverPort);
System.out.printf("Producer: Sending: %s\n", stringMsg);
aSocket.send(request); // send a message
byte[] buffer = new byte[1000];
DatagramPacket reply = new DatagramPacket(buffer, buffer.length);
aSocket.receive(reply); // wait for a reply
try {
Thread.sleep(2000); // have a small waiting period
} catch (InterruptedException e) {
}
}
} catch (SocketException e) {
System.out.println("Socket: " + e.getMessage());
} catch (IOException e) {
System.out.println("IO: " + e.getMessage());
} finally {
if (aSocket != null) aSocket.close();
}
}
/**
* Attempts to log a client in using the authentication server. Authentication server needs to run
* on the same host as the file server.
*
* @throws IOException Error reading from socket.
*/
private void login() throws IOException {
// set up required variables
DatagramSocket clientSocket = new DatagramSocket();
InetAddress authServerIP =
InetAddress
.getLocalHost(); // because authentication server runs on same host as file server
byte[] dataToSend;
byte[] receivedData = new byte[BUFFER_SIZE];
// get username and password
String userName = inFromClient.readLine().trim(); // get username
String password = inFromClient.readLine().trim(); // get password
dataToSend = new String(userName + " " + password).getBytes();
// send the username and password for processing by authentication server
DatagramPacket packetToSend =
new DatagramPacket(dataToSend, dataToSend.length, authServerIP, AUTHENTICATION_PORT);
clientSocket.send(packetToSend);
// receive the response from the authentication server
DatagramPacket receivedPacket = new DatagramPacket(receivedData, receivedData.length);
clientSocket.receive(receivedPacket);
String receivedString = new String(receivedPacket.getData()).trim();
receivedData = receivedString.getBytes();
if (receivedString.equals("yes")) {
outToClient.writeBytes(receivedString); // successful login
} else {
outToClient.writeBytes("no"); // unsuccessful login
}
}
public static void main(final String... args) throws Throwable {
final String remotehost = args[0];
final int remoteport = Integer.parseInt(args[1]);
final DatagramSocket socket = new DatagramSocket();
final byte buffer[] = new byte[512];
final InetSocketAddress remote = new InetSocketAddress(remotehost, remoteport);
buffer[0] = ENQUIRY;
buffer[1] = END_OF_TRANSMISSION;
socket.send(new DatagramPacket(buffer, 2, remote));
final DatagramPacket p = new DatagramPacket(buffer, buffer.length);
socket.receive(p);
if ((p.getLength() == 2) && (buffer[0] == ACKNOWLEDGE) && (buffer[1] == END_OF_TRANSMISSION))
System.out.println("Connection established");
else {
System.out.println("Connection failed");
return;
}
for (; ; ) {
int ptr = 0;
for (int d; (d = System.in.read()) != '\n'; ) buffer[ptr++] = (byte) d;
socket.send(new DatagramPacket(buffer, ptr, remote));
}
}
public static void doEcho(int port) throws IOException {
byte[] buf = new byte[BUF_SIZE];
DatagramPacket packet = new DatagramPacket(buf, buf.length);
DatagramSocket sock = new DatagramSocket(port);
System.out.println(
"Starting UDP echo on"
+ sock.getLocalAddress().getHostAddress()
+ ":"
+ sock.getLocalPort());
while (true) {
try {
sock.receive(packet);
sock.send(packet);
System.out.print(
"UDP From: "
+ packet.getAddress().getHostAddress()
+ ":"
+ packet.getPort()
+ "\n"
+ new String(packet.getData(), 0, packet.getLength())
+ "\n");
System.out.flush();
packet.setLength(buf.length);
// packet = new DatagramPacket(buf,buf.length);
} catch (IOException io_ex) {
}
}
}
public void run() {
System.out.println("ExeUDPServer开始监听..." + UDP_PORT);
DatagramSocket ds = null;
try {
ds = new DatagramSocket(UDP_PORT);
} catch (BindException e) {
System.out.println("UDP端口使用中...请重关闭程序启服务器");
} catch (SocketException e) {
e.printStackTrace();
}
while (ds != null) {
DatagramPacket dp = new DatagramPacket(buf, buf.length);
try {
ds.receive(dp);
// 得到把该数据包发来的端口和Ip
int rport = dp.getPort();
InetAddress addr = dp.getAddress();
String recvStr = new String(dp.getData(), 0, dp.getLength());
System.out.println("Server receive：" + recvStr + " from " + addr + " " + rport);
// 给客户端回应
String sendStr = "echo of " + recvStr;
byte[] sendBuf;
sendBuf = sendStr.getBytes();
DatagramPacket sendPacket = new DatagramPacket(sendBuf, sendBuf.length, addr, rport);
ds.send(sendPacket);
} catch (IOException e) {
e.printStackTrace();
}
}
}
public static void main(String args[]) throws Exception {
String serverHostname = args[0];
int portNumber = Integer.parseInt(args[1]);
try {
BufferedReader inFromUser = new BufferedReader(new InputStreamReader(System.in));
DatagramSocket clientSocket = new DatagramSocket();
InetAddress IPAddress = InetAddress.getByName(serverHostname);
System.out.println("Attempting to connect to " + IPAddress + ") via UDP port " + portNumber);
System.out.println("Enter \"Quit\" to exit program");
while (true) {
byte[] sendData = new byte[1024];
byte[] receiveData = new byte[1024];
System.out.print("Enter Message: ");
String sentence = inFromUser.readLine();
if (sentence.equals("Quit")) break;
sendData = sentence.getBytes();
System.out.println("Sending data to " + sendData.length + " bytes to server.");
DatagramPacket sendPacket =
new DatagramPacket(sendData, sendData.length, IPAddress, portNumber);
clientSocket.send(sendPacket);
DatagramPacket receivePacket = new DatagramPacket(receiveData, receiveData.length);
System.out.println("Waiting for return packet");
clientSocket.setSoTimeout(10000);
try {
clientSocket.receive(receivePacket);
String modifiedSentence = new String(receivePacket.getData());
InetAddress returnIPAddress = receivePacket.getAddress();
int port = receivePacket.getPort();
System.out.println("From server at: " + returnIPAddress + ":" + port);
System.out.println("Message: " + modifiedSentence);
} catch (SocketTimeoutException ste) {
System.out.println("Timeout Occurred: Packet assumed lost");
}
System.out.print("\n");
}
clientSocket.close();
} catch (UnknownHostException ex) {
System.err.println(ex);
} catch (IOException ex) {
System.err.println(ex);
}
}
private void enviar(byte[] frame) {
try {
socket.send(new DatagramPacket(frame, frame.length, remaddr, remport));
// System.out.println("Link envió algo ");
} catch (IOException e) {
// throw new NodeException(NodeException.EXCEPCION_ENVIO);
// System.out.println("Excepcion al enviar");
socket.close();
}
}
/** Generic constructor for the name service interface */
public LeetActive(String svc_host, int svc_port, int portNum) {
try {
nameServer = new DatagramSocket();
nameServer.setSoTimeout(3000);
nameServer.connect(InetAddress.getByName(svc_host), svc_port);
} catch (Exception e) {
System.err.println("LA " + e);
}
this.portNum = portNum;
hostList = new ArrayList();
}
void closeSocket() {
if (sock != null) {
// by sending a dummy packet, the thread will terminate (if it was flagged as stopped before)
sendDummyPacket(sock.getLocalAddress(), sock.getLocalPort());
sock.close();
sock = null;
if (Trace.trace) {
Trace.info("UDP.closeSocket()", "socket closed");
}
}
}
public void run() {
while (listen) {
try {
byte[] buf = new byte[256];
byte[] buf2 = new byte[256];
DatagramPacket packet = new DatagramPacket(buf, buf.length);
InetAddress address;
socket.receive(packet);
String in = new String(packet.getData(), 0, packet.getLength());
address = packet.getAddress();
int port = packet.getPort();
// newClient = findPort(port, address, newClient);
String name = findPerson(port, address);
// System.out.println(name);
if (in.startsWith("1")) {
String nama = new String(packet.getData(), 0, packet.getLength());
nama = nama.substring(1);
newClient = new Client(packet.getAddress(), packet.getPort(), nama);
threads.add(newClient);
String wel =
"\nWelcome "
+ newClient.nama
+ "\n "
+ "to quit type \"bye\" and to whisper use prefix @name : ";
buf = (wel).getBytes();
packet = new DatagramPacket(buf, buf.length, packet.getAddress(), packet.getPort());
socket.send(packet);
wel = " enters the room";
buf = (newClient.nama + wel).getBytes();
Broadcast(address, port, buf);
} else if (in.startsWith("@")) {
// findPort(port, address, newClient);
Whisper(newClient, packet.getData());
} else if (in.equals("bye")) {
String bye = name + " is leaving";
buf2 = bye.getBytes();
// packet = new DatagramPacket(buf,buf.length,newClient.address, newClient.port);
Broadcast(address, port, buf2);
} else {
byte[] buf3 = new byte[256];
String text =
name + "<broadcast> : " + new String(packet.getData(), 0, packet.getLength());
buf3 = text.getBytes();
Broadcast(packet.getAddress(), packet.getPort(), buf3);
}
} catch (IOException ex) {
Logger.getLogger(DatagramServer.class.getName()).log(Level.SEVERE, null, ex);
}
}
socket.close();
}
private void passFileDescriptor(LocalSocket fdSocket, FileDescriptor tunFD) throws Exception {
OutputStream outputStream = fdSocket.getOutputStream();
InputStream inputStream = fdSocket.getInputStream();
try {
BufferedReader reader = new BufferedReader(new InputStreamReader(inputStream), 1);
String request = reader.readLine();
String[] parts = request.split(",");
LogUtils.i("current open tcp sockets: " + tcpSockets.size());
LogUtils.i("current open udp sockets: " + udpSockets.size());
if ("TUN".equals(parts[0])) {
fdSocket.setFileDescriptorsForSend(new FileDescriptor[] {tunFD});
outputStream.write('*');
} else if ("OPEN UDP".equals(parts[0])) {
String socketId = parts[1];
passUdpFileDescriptor(fdSocket, outputStream, socketId);
} else if ("OPEN TCP".equals(parts[0])) {
String socketId = parts[1];
String dstIp = parts[2];
int dstPort = Integer.parseInt(parts[3]);
int connectTimeout = Integer.parseInt(parts[4]);
passTcpFileDescriptor(fdSocket, outputStream, socketId, dstIp, dstPort, connectTimeout);
} else if ("CLOSE UDP".equals(parts[0])) {
String socketId = parts[1];
DatagramSocket sock = udpSockets.get(socketId);
if (sock != null) {
udpSockets.remove(socketId);
sock.close();
}
} else if ("CLOSE TCP".equals(parts[0])) {
String socketId = parts[1];
Socket sock = tcpSockets.get(socketId);
if (sock != null) {
tcpSockets.remove(socketId);
sock.close();
}
} else {
throw new UnsupportedOperationException("fdsock unable to handle: " + request);
}
} finally {
try {
inputStream.close();
} catch (Exception e) {
LogUtils.e("failed to close input stream", e);
}
try {
outputStream.close();
} catch (Exception e) {
LogUtils.e("failed to close output stream", e);
}
fdSocket.close();
}
}
public static void main(String args[]) {
try {
DatagramSocket d1 = new DatagramSocket(2071);
DatagramSocket d2 = new DatagramSocket(2081);
UDPSender s = new UDPSender(d1);
UDPReceiver r = new UDPReceiver(d2);
s.t.join();
r.t.join();
d1.close();
d2.close();
} catch (Exception e) {
}
}
public static void main(String[] args) {
try (DatagramSocket socket = new DatagramSocket(0)) {
socket.setSoTimeout(10000);
InetAddress host = InetAddress.getByName(HOSTNAME);
DatagramPacket request = new DatagramPacket(new byte[1], 1, host, PORT);
DatagramPacket response = new DatagramPacket(new byte[1024], 1024);
socket.send(request);
socket.receive(response);
String result = new String(response.getData(), 0, response.getLength(), "US-ASCII");
System.out.println(result);
} catch (IOException ex) {
ex.printStackTrace();
}
}
public static void main(String args[]) throws Exception {
final int ENOUGH_SIZE = 1024;
final int SMALL_SIZE = 4;
boolean isBlocked = true;
int size = ENOUGH_SIZE;
if (args.length > 0) {
int opt = Integer.parseInt(args[0]);
switch (opt) {
case 1:
isBlocked = true;
size = ENOUGH_SIZE;
break;
case 2:
isBlocked = true;
size = SMALL_SIZE;
break;
case 3:
isBlocked = false;
size = ENOUGH_SIZE;
break;
case 4:
isBlocked = false;
size = SMALL_SIZE;
break;
}
}
DatagramChannel channel = DatagramChannel.open();
channel.configureBlocking(isBlocked);
ByteBuffer buffer = ByteBuffer.allocate(size);
DatagramSocket socket = channel.socket();
SocketAddress localAddr = new InetSocketAddress(8000);
socket.bind(localAddr);
while (true) {
System.out.println("开始接收数据报");
SocketAddress remoteAddr = channel.receive(buffer);
if (remoteAddr == null) {
System.out.println("没有接收到数据报");
} else {
buffer.flip();
System.out.println("接收到的数据报的大小为" + buffer.remaining());
}
Thread.sleep(500);
}
}
public static void Whisper(Client newClient, byte[] buf) {
String input = new String(buf, 0, buf.length);
input = input.substring(1);
byte[] sendbuff = new byte[256];
String[] parts = null;
String text = null;
String whisperTo = null;
try {
parts = input.split(" : ");
whisperTo = parts[0]; // 004
// System.out.println(newClient.nama+" "+whisperTo);
text = parts[1];
} catch (ArrayIndexOutOfBoundsException e) {
String notif = "wrong prefix";
sendbuff = notif.getBytes();
DatagramPacket packet =
new DatagramPacket(sendbuff, sendbuff.length, newClient.address, newClient.port);
}
String prefix = newClient.nama + " : " + text;
sendbuff = prefix.getBytes();
for (Client h : threads) {
if (h.nama.equals(whisperTo)) {
DatagramPacket packet = new DatagramPacket(sendbuff, sendbuff.length, h.address, h.port);
try {
socket.send(packet);
} catch (IOException ex) {
Logger.getLogger(DatagramServer.class.getName()).log(Level.SEVERE, null, ex);
}
}
}
}
public void run() {
while (true) {
DatagramPacket msg = new DatagramPacket(new byte[1000], 1000);
try {
socket.receive(msg);
} catch (IOException e) {
}
;
String container = new String(msg.getData());
container = container.trim();
if (container.substring(0, container.indexOf(' ')).equals("vfd"))
CALM.box.mailAction(container.substring(container.indexOf(' ') + 1, container.length()));
else if (container.substring(0, container.indexOf(' ')).equals("dfv"))
CALM.box.mailAction2(container.substring(container.indexOf(' ') + 1, container.length()));
}
}
private void listen() throws Exception {
System.out.println("Listening on port: " + serverPort);
// Initialize socket
socket = new DatagramSocket(serverPort);
// While running
while (run) {
// Wait for handshake
packet = new DatagramPacket(response, response.length);
socket.receive(packet); // Blocking
// System.out.println("RT: got packet");
Packet p = new Packet(packet.getData());
if (p.isHandshake()) {
// System.out.println("RT: is handshake");
// Get client connection info
InetAddress IPAddress = packet.getAddress();
int port = packet.getPort();
// Process handshake
processHandshake(p, IPAddress, port);
// Get message
MyMessage message = getMessage();
if (message != null) {
rc.rreceive(message);
}
}
}
}
public void destory() {
procMsgThd.stop0();
procMsgThd.interrupt();
mainThread.interrupt();
if (group != null) {
try {
if (recvSocket instanceof MulticastSocket) {
((MulticastSocket) recvSocket).leaveGroup(group);
}
} catch (IOException ioe) {
}
}
sendSocket.close();
recvSocket.close();
}
/**
* Workaround for the problem encountered in certains JDKs that a thread listening on a socket
* cannot be interrupted. Therefore we just send a dummy datagram packet so that the thread 'wakes
* up' and realizes it has to terminate. Should be removed when all JDKs support
* Thread.interrupt() on reads. Uses sock t send dummy packet, so this socket has to be still
* alive.
*
* @param dest The destination host. Will be local host if null
* @param port The destination port
*/
void sendDummyPacket(InetAddress dest, int port) {
DatagramPacket packet;
byte[] buf = {0};
if (dest == null) {
try {
dest = InetAddress.getLocalHost();
} catch (Exception e) {
}
}
if (Trace.debug) {
Trace.info("UDP.sendDummyPacket()", "sending packet to " + dest + ":" + port);
}
if (sock == null || dest == null) {
Trace.warn(
"UDP.sendDummyPacket()", "sock was null or dest was null, cannot send dummy packet");
return;
}
packet = new DatagramPacket(buf, buf.length, dest, port);
try {
sock.send(packet);
} catch (Throwable e) {
Trace.error(
"UDP.sendDummyPacket()",
"exception sending dummy packet to " + dest + ":" + port + ": " + e);
}
}
void doSend(byte[] data, InetAddress dest, int port) throws IOException {
DatagramPacket packet;
packet = new DatagramPacket(data, data.length, dest, port);
if (sock != null) {
sock.send(packet);
}
}
public UDPEcho(String host, int port) throws IOException, UnknownHostException {
this.hostIP = InetAddress.getByName(host);
this.port = port;
sock = new DatagramSocket();
System.out.println("UDP: " + sock.getLocalAddress() + ":" + sock.getLocalPort());
// sock.connect(hostIP,port);
}
