// This method is called when a request has been made to close a client connection
public synchronized void disconnectClient(ClientConnection clientConnection) {
// Ensures this connection exists (a necessary check when this is being called from outside of a
// clientConnection)
if (clientConnection != null
&& clientConnection.isConnected()
&& clientSocketList.get(clientSocketList.indexOf(clientConnection)) != null) {
// Send the client a message telling it to close its socket
clientConnection.xmitMessage(ClientConnection.QUIT);
// Then close that socket...the user really doesn't have a choice. We're just asking to be
// nice.
clientSocketList.get(clientSocketList.indexOf(clientConnection)).closeSocket();
parent.updateStatusBox(
clientSocketList.indexOf(clientConnection)
+ " "
+ "Forcing disconnection of client "
+ clientConnection.id
+ " on port "
+ port
+ "...");
} else {
// If this thread is NOT connected, it may be stuck, so let's send an interrupt to wake it up
clientThreadList.get(clientSocketList.indexOf(clientConnection)).interrupt();
parent.updateStatusBox("Closing listen socket on port " + port + "...");
}
}
// This method sets a boolean value that tells the server to leave the socket generation loop and
// begin cleanup
public void notifyStopPressed() {
stopPressed = true;
parent.getServerThread().interrupt();
try {
if (serverSocket != null) {
serverSocket.close();
}
} catch (IOException e) {
parent.updateStatusBox(e.getMessage());
}
}
// This method is called when a client has disconnected from the server and its thread is about to
// end
// It just presents a status message and removes the given client and thread from our lists
public synchronized void clientThreadEnding(ClientConnection clientConnection) {
parent.updateStatusBox(
clientSocketList.indexOf(clientConnection)
+ " "
+ "Client "
+ clientConnection.id
+ " disconnected, removing from connection pool");
clientThreadList.remove(clientSocketList.indexOf(clientConnection));
clientSocketList.remove(clientSocketList.indexOf(clientConnection));
numClients--;
parent.updateStatusBox("There are " + numClients + " clients connected");
}
// Once a client is connected to the server, their connection object is handed off to this method
// for handling
public synchronized void clientConnected(Socket socket) {
// Create a ClientConnection to contain this new client, pass off the socket, and start the new
// thread
ClientConnection clientConnection = new ClientConnection(this, socket, idCounter);
Thread clientSocketThread = new Thread(clientConnection);
clientSocketThread.start();
// Add this connection to our socket and thread lists so we can keep track of who is alive
clientSocketList.add(clientConnection);
clientThreadList.add(clientSocketList.indexOf(clientConnection), clientSocketThread);
numClients++; // numClients just keeps track of how many clients are connected
idCounter++; // idCounter NEVER decrements, so we will never have two clientConnections trying
// to occupy
// the same space in the vector
// Let the server status box know that someone has connected
parent.updateStatusBox("Client " + clientConnection.id + " has connected on port " + port);
parent.updateStatusBox("There are " + numClients + " clients connected\n");
}
// This method starts the voting process
public void startVote() {
this.voting = true; // Status boolean
broadcastMsg("/numq" + numQuestions); // Let all clients know how many questions are coming
for (int x = 0; x <= (numQuestions - 1); x++) {
broadcastMsg("/ques" + x + questions[x]); // Send each question in turn to the clients
}
// Tell the clients that voting has started (doubles as a "no more questions" notification
broadcastMsg("/stvt");
parent.updateStatusBox("Voting started! " + numQuestions + " questions presented to clients.");
}
// This method stops the voting process
public void stopVote() {
this.voting = false; // Status boolean
for (int x = 0; x <= (numQuestions - 1); x++) {
broadcastMsg(
"/ansr" + x + votes[x]); // Tells all clients how many votes were cast for each question
}
broadcastMsg("/novo"); // Tells all users that voting has ended
parent.updateStatusBox(
"Voting has ended! Voting Results: \n1: "
+ votes[0]
+ " \n2: "
+ votes[1]
+ " \n3: "
+ votes[2]
+ " \n4: "
+ votes[3]);
// Perform some simple math to calculate the vote winner, then let the server know which option
// won
int largest = 0;
int winner = 0;
for (int x = 0; x <= 3; x++) {
if (votes[x] > largest) {
largest = votes[x];
winner = (x + 1);
}
}
parent.updateStatusBox("Option " + winner + " was reported as the winner.");
for (int x = 0; x <= 3; x++) {
this.votes[x] = 0;
}
}
// This method keeps track of how many votes have been cast, useful for letting the server manager
// know when to stop a vote
public void setVote(int voteNo) {
this.votes[voteNo]++;
int totalVotes = votes[0] + votes[1] + votes[2] + votes[3];
int votesRemaining = numClients - totalVotes;
broadcastMsg("/rem" + votesRemaining);
parent.updateStatusBox(
totalVotes
+ " votes cast out of "
+ numClients
+ " clients. "
+ votesRemaining
+ " votes remain.");
}
// RUN METHOD
public void run() {
for (int x = 0; x <= 3; x++) {
selected[x] = false;
questions[x] = "";
}
// Create new lists for the clients and threads
if (clientSocketList == null || !clientSocketList.isEmpty()) {
clientSocketList = new Vector<ClientConnection>();
}
if (clientThreadList == null || !clientThreadList.isEmpty()) {
clientThreadList = new Vector<Thread>();
}
// Now we're ready to go
isRunning = true;
stopPressed = false;
// Server initialization
parent.updateStatusBox("SERVER ONLINE");
parent.setStatus(new Color(32, 160, 32), "ONLINE");
parent.setButtonEnabled(parent.STOP_BUTTON, true);
Socket clientSocket = null;
// SERVER CONNECTION LOOP AND CLIENT THREAD GENERATION
while (!stopPressed) {
try {
// Create a new socket and wait for a client connection
parent.updateStatusBox("Listening for clients on port: " + String.valueOf(port));
serverSocket = new ServerSocket(port);
clientSocket = serverSocket.accept();
// Once a connection is established, we pass it off to clientConnected, which creates a new
// thread
// to manage this client
clientConnected(clientSocket);
} catch (IOException e) {
// No need to implement anything here -- cleanup is taken care of outside the loop
// TODO: Move cleanup to a FINALLY block
parent.updateStatusBox(e.getMessage());
} finally {
try {
if (serverSocket != null) {
serverSocket.close();
}
} catch (IOException e) {
parent.updateStatusBox(e.getMessage());
}
}
}
// We're responsible adults...once we leave the server connection loop, we need to clean up
// (close all
// connections) before we can officially stop the server.
parent.updateStatusBox("Stopping server...");
// Instead of locking clientSocketList inside of a huge synchronized block, just make a copy of
// it
// This is a good idea because as clients disconnect, they will be asking to remove
// themselves from
// the clientSocketList, and we don't want them to wait
Vector<ClientConnection> snapshot = new Vector<ClientConnection>();
snapshot.addAll(clientSocketList);
Iterator<ClientConnection> clientIterator = snapshot.iterator();
ClientConnection clientConnection;
// This loop iterates through all of the currently connected clients and disconnects them
while (clientIterator.hasNext()) {
clientConnection = clientIterator.next();
parent.updateStatusBox("Stopping client from ServerRunnable Loop");
disconnectClient(clientConnection);
}
snapshot.clear();
// Once we've cleaned up, we let the user know that the server is down and re-enable the Start
// Server button
parent.updateStatusBox("\nSERVER SHUTDOWN COMPLETE");
parent.setStatus(Color.RED, "OFFLINE");
isRunning = false;
parent.setButtonEnabled(parent.GO_BUTTON, true);
}