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());
}
}
