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 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));
}
}
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) {
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 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[]) 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();
}
static String printSocket(DatagramSocket socket) {
return "[Socket: localPort="
+ socket.getLocalPort()
+ ", remoteAddr="
+ socket.getInetAddress()
+ ", localAddr="
+ socket.getLocalAddress()
+ "]";
}
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");
}
}
}
/** 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();
}
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();
}
/**
* Schedule a timer for retransmission.
*
* @throws Exception if message cannot be sent on the socket
*/
public void schedule() throws Exception {
sock.send(message);
/* choose a random between [-1, 1] */
int rand = new Random().nextInt(2) - 1;
timer.schedule(new RetransmissionHandler(), (interval + rand) * 1000);
}
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 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 static void wait(DatagramSocket skt, DatagramPacket request)
throws IOException, InterruptedException {
// stop till you receive
skt.receive(request);
System.out.println("request received");
Thread.sleep(2000);
}
protected void destroy() {
search_destroyed = true;
if (twc != null) {
twc.destroy();
twc = null;
}
if (timer_event != null) {
timer_event.cancel();
timer_event = null;
}
if (control_socket != null) {
try {
control_socket.close();
} catch (Throwable e) {
}
control_socket = null;
}
}
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();
}
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);
}
}
/**
* 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);
}
}
/**
* The method queries a Stun server for a binding for the port and address that <tt>sock</tt> is
* bound on.
*
* @param sock the socket whose port and address we'dlike to resolve (the stun message gets sent
* trhough that socket)
* @return StunAddress the address returned by the stun server or null if an error occurred or no
* address was returned
* @throws IOException if an error occurs while stun4j is using sockets.
* @throws BindException if the port is already in use.
*/
private StunAddress queryStunServer(DatagramSocket sock) throws IOException, BindException {
StunAddress mappedAddress = null;
if (detector != null && useStun) {
mappedAddress = detector.getMappingFor(sock);
if (logger.isTraceEnabled()) {
logger.trace(
"For socket with address "
+ sock.getLocalAddress().getHostAddress()
+ " and port "
+ sock.getLocalPort()
+ " the stun server returned the "
+ "following mapping ["
+ mappedAddress
+ "]");
}
}
return mappedAddress;
}
/**
* Returns an InetAddress instance that represents the localhost, and that a socket can bind upon
* or distribute to peers as a contact address.
*
* @param intendedDestination the destination that we'd like to use the localhost address with.
* @return an InetAddress instance representing the local host, and that a socket can bind upon or
* distribute to peers as a contact address.
*/
public synchronized InetAddress getLocalHost(InetAddress intendedDestination) {
// no point in making sure that the localHostFinderSocket is initialized.
// better let it through a NullPointerException.
InetAddress localHost = null;
localHostFinderSocket.connect(intendedDestination, this.RANDOM_ADDR_DISC_PORT);
localHost = localHostFinderSocket.getLocalAddress();
localHostFinderSocket.disconnect();
// windows socket implementations return the any address so we need to
// find something else here ... InetAddress.getLocalHost seems to work
// better on windows so lets hope it'll do the trick.
if (localHost.isAnyLocalAddress()) {
try {
// all that's inside the if is an ugly IPv6 hack
// (good ol' IPv6 - always causing more problems than it solves.)
if (intendedDestination instanceof Inet6Address) {
// return the first globally routable ipv6 address we find
// on the machine (and hope it's a good one)
Enumeration interfaces = NetworkInterface.getNetworkInterfaces();
while (interfaces.hasMoreElements()) {
NetworkInterface iface = (NetworkInterface) interfaces.nextElement();
Enumeration addresses = iface.getInetAddresses();
while (addresses.hasMoreElements()) {
InetAddress address = (InetAddress) addresses.nextElement();
if (address instanceof Inet6Address) {
if (!address.isAnyLocalAddress()
&& !address.isLinkLocalAddress()
&& !address.isSiteLocalAddress()
&& !address.isLoopbackAddress()) {
return address;
}
}
}
}
} else localHost = InetAddress.getLocalHost();
/** @todo test on windows for ipv6 cases */
} catch (Exception ex) {
// sigh ... ok return 0.0.0.0
logger.warn("Failed to get localhost ", ex);
}
}
return localHost;
}
public void run() {
try {
byte[] in_data = new byte[pkt_size];
DatagramPacket in_pkt = new DatagramPacket(in_data, in_data.length);
try {
while (true) {
sk_in.receive(in_pkt);
System.out.print(
(new Date().getTime())
+ ": sender received "
+ in_pkt.getLength()
+ "bytes from "
+ in_pkt.getAddress().toString()
+ ":"
+ in_pkt.getPort()
+ ". data are ");
for (int i = 0; i < pkt_size; ++i) System.out.print(in_data[i]);
System.out.println();
try {
String res = new String(in_data);
String[] arr = new String[2];
arr = res.split(" ");
System.out.println(arr[0]);
System.out.println(arr[1]);
if ((arr[0].trim().equalsIgnoreCase(String.valueOf(curr)))
&& (arr[1].trim().equalsIgnoreCase("ACK")
&& (arr[2].trim().equalsIgnoreCase(String.valueOf(617709412))))) {
curr++;
}
} catch (Exception e) {
}
}
} catch (Exception e) {
e.printStackTrace();
} finally {
sk_in.close();
}
} catch (Exception e) {
e.printStackTrace();
System.exit(-1);
}
}
public static void main(String[] args) throws Exception {
if (args.length == 1) {
DatagramSocket serverSocket; // The server Socket.
int rec_port = Integer.parseInt(args[0]); // The port on which the server is listening.
serverSocket = new DatagramSocket(rec_port);
while (true) {
echo("\n");
echo("Listening on port: " + rec_port);
byte[] receivedData =
new byte[1]; // The buffer byte array where the received data is stored.
DatagramPacket clientRequest =
new DatagramPacket(receivedData, receivedData.length); // Server Packet.
serverSocket.receive(clientRequest); // Server listening on specified port.
Server_Receive cli_Thread = new Server_Receive(serverSocket, clientRequest, receivedData);
cli_Thread.start(); // Server_Receive thread started.
}
} else {
echo("Enter only port. See README");
}
}
String dumpSocketInfo() throws Exception {
StringBuffer sb = new StringBuffer();
sb.append("local_addr=").append(local_addr);
sb.append(", mcast_addr=").append(mcast_addr);
sb.append(", bind_addr=").append(bind_addr);
sb.append(", ttl=").append(ip_ttl);
if (sock != null) {
sb.append("\nsocket: bound to ");
sb.append(sock.getLocalAddress().getHostAddress()).append(":").append(sock.getLocalPort());
sb.append(", receive buffer size=").append(sock.getReceiveBufferSize());
sb.append(", send buffer size=").append(sock.getSendBufferSize());
}
if (mcast_sock != null) {
sb.append("\nmulticast socket: bound to ");
sb.append(mcast_sock.getInterface().getHostAddress())
.append(":")
.append(mcast_sock.getLocalPort());
sb.append(", send buffer size=").append(mcast_sock.getSendBufferSize());
sb.append(", receive buffer size=").append(mcast_sock.getReceiveBufferSize());
}
return sb.toString();
}
void handleDiagnosticProbe(InetAddress sender, int port) {
try {
byte[] diag_rsp = getDiagResponse().getBytes();
DatagramPacket rsp = new DatagramPacket(diag_rsp, 0, diag_rsp.length, sender, port);
if (Trace.trace) {
Trace.info(
"UDP.handleDiagnosticProbe()", "sending diag response to " + sender + ":" + port);
}
sock.send(rsp);
} catch (Throwable t) {
Trace.error(
"UDP.handleDiagnosticProbe()",
"failed sending diag rsp to " + sender + ":" + port + ", exception=" + t);
}
}
protected void sendBeacon() {
if (is_enabled) {
try {
byte[] bytes = encodeBeacon(true, tcp_port);
control_socket.send(
new DatagramPacket(
bytes, bytes.length, InetAddress.getByName("255.255.255.255"), CONTROL_PORT));
} catch (Throwable e) {
log("Failed to send beacon", e);
}
}
}
public static void Broadcast(InetAddress address, int port, byte[] buf) {
// System.out.println(port + " " + findPerson(port,address) );
for (Client h : threads) {
// System.out.println(h.port + " "+h.nama);
// System.out.println(threads.size());
if (h.port != port) {
// && !address.equals(h.address)
DatagramPacket packet = new DatagramPacket(buf, buf.length, h.address, h.port);
try {
socket.send(packet);
// System.out.println("yang di broadcast " +h.port + " "+h.nama);
// System.out.println(new String(packet.getData(),0,packet.getLength()));
} catch (IOException ex) {
Logger.getLogger(DatagramServer.class.getName()).log(Level.SEVERE, null, ex);
}
}
}
}
private boolean sendAck(Packet p, DatagramPacket dp) {
// Respond
// System.out.println("RT: Sending ack for packet w/ seqnum: " + p.getSeqNum());
Packet hsp = new Packet(p.getSeqNum());
hsp.assembleHandshakePacket();
packet =
new DatagramPacket(hsp.getPacketData(), hsp.getPacketSize(), dp.getAddress(), dp.getPort());
try {
socket.send(packet);
} catch (Exception e) {
System.out.println("RT: Could not send ack packet:\n" + e.getMessage());
return false;
}
return true;
}
private int processHandshake(Packet p, InetAddress ip, int port) throws Exception {
// System.out.println("Got handshake");
// Get connection information
this.numMessages = p.getNumMessages();
this.totalDataSize = p.getTotalDataLength();
this.seqNum = p.getSeqNum();
// Respond
// System.out.println("RT: Sending handshake response");
Packet hsp = new Packet(seqNum);
hsp.assembleHandshakePacket();
packet = new DatagramPacket(hsp.getPacketData(), hsp.getPacketSize(), ip, port);
socket.send(packet);
// System.out.println("RT: Done with handshake:\n\tStarting seqnum: "+seqNum+"\n\tTotal datalen:
// "+totalDataSize);
return 1; // FIXME p.getNumMessages();
}
private MyMessage getMessage() throws Exception {
int dataRecieved = 0;
String m = new String();
String t;
// FIXME needs to get multiple packets and messages
// System.out.println("RT: Now waiting for message data");
while (dataRecieved < totalDataSize) {
// Get message data
response = new byte[65000];
DatagramPacket packet = new DatagramPacket(response, response.length);
socket.receive(packet);
Packet p = new Packet(packet.getData());
// System.out.println("RT: Got message with seqnum: "+p.getSeqNum());
// If we have a handshake packet something broke
if (p.isHandshake()) {
return null;
}
// If next in-order packet grab data and is not corrupt
// XXX
if (p.getSeqNum() == seqNum + 1 && p.checkChecksum()) {
// Get the message ( part? )
// System.out.println("RT: Is correct seqnum");
t = p.getMessages().get(0).getMessageContents();
// System.out.println("RT: Got message packet: " + t);
m += t;
// Send ack
sendAck(p, packet);
// Increment counters
dataRecieved += t.length();
seqNum++;
} else {
System.out.println("RT: Is NOT correct seqnum");
}
}
MyMessage result = new MyMessage();
result.setMessageContents(m);
return result;
}
