public static boolean checkMessage(String s1, String s2, SocketChannel sc) {
if (s1 == null || s1 == null) {
sendMessage(sc, MessageUtils.message("<server>", "bad message"));
System.out.println("Bad message from " + getNickFromSocket(sc));
return false;
}
return true;
}
public static void main(String args[]) throws Exception {
InputStreamReader isr = new InputStreamReader(System.in);
BufferedReader br = new BufferedReader(isr);
StringTokenizer tokenizer;
String curCommand;
String str = "";
String nickname = "";
if (args.length == 0) {
System.err.println("Usage: nickname\n");
System.exit(1);
} else {
nickname = args[0];
}
while (true) {
curCommand = "";
try {
str = br.readLine();
} catch (Exception ex) {
System.err.println("Input canceled: " + ex.getMessage());
System.exit(1);
}
tokenizer = new StringTokenizer(str, " \t");
if (tokenizer.hasMoreTokens()) {
curCommand = tokenizer.nextToken();
}
if (curCommand.equals("/connect")) {
if (tokenizer.countTokens() != 1) {
System.err.println("Connect usage: /connect host:portNumber");
} else {
String hostPort = tokenizer.nextToken();
int hostPortSeparator = hostPort.indexOf(':');
if (hostPortSeparator == -1) {
System.err.println("Connect usage: /connect host:portNumber");
continue;
}
String host = hostPort.substring(0, hostPort.indexOf(':'));
int port;
try {
port = Integer.parseInt(hostPort.substring(hostPort.indexOf(':') + 1));
} catch (Exception ex) {
System.err.println("Invalid hostPort: " + hostPort);
continue;
}
System.out.println(host + ":" + port);
if (servers.containsKey(host)) {
System.out.println("You are already connected to this host");
} else {
new Client(host, port, nickname);
}
}
} else if (curCommand.equals("/disconnect")) {
if (tokenizer.countTokens() != 0) {
System.err.println("Disconnect usage: /disconnect");
} else {
disconnect(true);
}
} else if (curCommand.equals("/whereami")) {
if (Client.isConnected) {
System.out.println("You are using this host: " + Client.curHost);
} else {
System.out.println("You haven't connected yet.");
}
} else if (curCommand.equals("/list")) {
if (tokenizer.countTokens() != 0) {
System.err.println("List usage: /list");
} else {
list();
}
} else if (curCommand.equals("/use")) {
if (tokenizer.countTokens() != 1) {
System.err.println("Use usage: /use host");
} else {
use(tokenizer.nextToken());
}
} else if (curCommand.equals("/exit")) {
if (tokenizer.countTokens() != 0) {
System.err.println("Exit usage: /exit");
} else {
exit();
}
} else {
if (Client.isConnected) {
send(curSocketChannel, MessageUtils.message(nickname, str));
} else {
System.err.println("You haven't got connection yet.");
}
}
}
}
public static void checkClients(List<SocketChannel> anonymousClients) {
try {
if (selector.selectNow() == 0) {
return;
}
Set<SelectionKey> keys = selector.selectedKeys();
for (SelectionKey key : keys) {
if ((key.readyOps() & SelectionKey.OP_ACCEPT) == SelectionKey.OP_ACCEPT) {
SocketChannel clientSocket = serverSocket.accept();
if (clientSocket == null) {
System.err.println("Error: can not accept");
continue;
}
anonymousClients.add(clientSocket);
clientSocket.configureBlocking(false);
clientSocket.register(selector, SelectionKey.OP_READ);
} else if ((key.readyOps() & SelectionKey.OP_READ) == SelectionKey.OP_READ) {
SocketChannel clientSocket = (SocketChannel) key.channel();
ByteBuffer bytes = ByteBuffer.allocate(4096);
if (clientSocket.read(bytes) != -1) {
byte[] message = bytes.array();
switch (message[0]) {
case 1:
{
String nick = MessageUtils.parseMessage(message).first;
if (!checkMessage(nick, "", clientSocket)) {
continue;
}
if (clients.containsKey(nick) || nick.length() > 32) {
if (nick.length() > 32) {
sendMessage(
clientSocket, MessageUtils.error("<server>: your nick is too long"));
} else {
sendMessage(
clientSocket,
MessageUtils.error("<server>: another user is using this nick"));
}
sendMessage(clientSocket, MessageUtils.bye());
anonymousClients.remove(clientSocket);
Utils.tryClose(clientSocket);
} else {
System.out.println(nick + " enter this chatroom");
notifyAllClients(nick + " enter this chatroom");
sendMessage(
clientSocket,
MessageUtils.message("<server>", "Wellcome, your nick is " + nick));
anonymousClients.remove(clientSocket);
clients.put(nick, clientSocket);
}
break;
}
case 2:
{
String nick = getNickFromSocket(clientSocket);
if (nick == null) {
Utils.printErrorAndExit("Error: it could not happen");
}
Utils.Pair<String, String> pair = MessageUtils.parseMessage(message);
if (!checkMessage(pair.first, pair.second, clientSocket)) {
continue;
}
if (!pair.first.equals(nick)) {
System.out.println("Cheater: " + nick);
sendMessage(clientSocket, MessageUtils.message("<server>", "do not cheat"));
}
for (Entry<String, SocketChannel> client : clients.entrySet()) {
if (!clientSocket.equals(client.getValue())) {
sendMessage(client.getValue(), MessageUtils.message(nick, pair.second));
}
}
break;
}
case 3:
disconnectClient(clientSocket);
break;
case 127:
{
String nick = getNickFromSocket(clientSocket);
Utils.Pair<String, String> pair = MessageUtils.parseMessage(message);
if (!checkMessage(pair.first, pair.second, clientSocket)) {
continue;
}
if (!pair.first.equals(nick)) {
System.out.println("Cheater: " + nick);
sendMessage(clientSocket, MessageUtils.message("<server>", "do not cheat"));
}
System.out.println(nick + ": " + pair.second);
break;
}
default:
System.out.println("Bad message from " + getNickFromSocket(clientSocket));
sendMessage(clientSocket, MessageUtils.message("<server>", "bad message"));
break;
}
} else {
disconnectClient(clientSocket);
}
}
}
keys.clear();
} catch (Exception expt) {
expt.printStackTrace();
Utils.printErrorAndExit(expt.getMessage());
}
}
public static void readCommand() {
try {
if (!reader.ready()) {
return;
}
StringTokenizer tokens = new StringTokenizer(reader.readLine());
if (tokens.hasMoreTokens()) {
switch (tokens.nextToken()) {
case "/listen":
listen(tokens);
break;
case "/stop":
stop();
break;
case "/list":
if (port[0] == -1) {
System.err.println("Error: start listening before");
}
for (Entry<String, SocketChannel> client : clients.entrySet()) {
System.out.println(client.getKey());
}
if (clients.entrySet().isEmpty()) {
System.out.println("list: no clients online");
}
break;
case "/send":
if (tokens.hasMoreTokens()) {
String name = tokens.nextToken();
if (clients.containsKey(name)) {
if (tokens.hasMoreTokens()) {
sendMessage(
clients.get(name),
MessageUtils.message("<server>", getMessageFromTokens(tokens)));
} else {
System.err.println("send: message is empty");
}
} else {
System.err.println("send: no such client");
}
} else {
System.err.println("send: no client name");
}
break;
case "/sendall":
if (tokens.hasMoreTokens()) {
notifyAllClients(getMessageFromTokens(tokens));
} else {
System.err.println("sendall: message is empty");
}
break;
case "/kill":
kill(tokens);
break;
case "/exit":
if (port[0] != -1) {
stop();
}
Utils.tryClose(selector);
System.exit(0);
break;
default:
System.err.print("Error: unknown command");
break;
}
} else {
System.err.println("Error: empty input");
}
} catch (Exception expt) {
Utils.printErrorAndExit(expt.getMessage());
}
}
public static void notifyAllClients(String message) {
for (Entry<String, SocketChannel> client : clients.entrySet()) {
sendMessage(client.getValue(), MessageUtils.message("<server>", message));
}
}