I"m working on a Client-Server chat program for a university project and I have little programming background. I've made 3 classes: ChatClient, ChatServer and ChatServerThread. I can currently have multiple clients connected and talking to the server at any time.
Although one of the requirements that I'm having the most difficulty is this: "Any message typed from 1 client is sent to all other clients" and also "Both sent and received messages should be displayed".
I've spent the last few nights just trying to get this extra bit of functionality working but have had no luck.
I've been reading and looking around for a while but I have lots of difficulty adapting online examples to my work. I've read that I should be creating a list of sockets and then iterate through the list and send data to everyone in the list, which makes sense in my head but gives me a headache when I try implementing it. Any help with this would be very greatly appreciated. Extra points if anyone can give me some insight on how I could encrypt the sent data.
ChatClient
import java.net.*;
import java.io.*;
public class ChatClient {
private Socket socket = null;
private DataInputStream console = null;
private DataOutputStream streamOut = null;
private String myName = null;
private BufferedReader StreamIn = null;
private String response = null;
public ChatClient(String serverName, int serverPort) {
try {
console = new DataInputStream(System.in);
System.out.println("What is your name?");
myName = console.readLine();
System.out.println(myName + " <" + InetAddress.getLocalHost() + "> ");
} catch (IOException ioe) {
System.out.println("Unexpected exception: " + ioe.getMessage());
}
System.out.println("Establishing connection. Please wait ...");
try {
socket = new Socket(serverName, serverPort);
System.out.println("Connected: " + socket);
StreamIn = new BufferedReader(new InputStreamReader(socket.getInputStream()));
streamOut = new DataOutputStream(socket.getOutputStream());
streamOut.writeUTF(":" + myName + " <" + InetAddress.getLocalHost() + "> HAS JOINED");
streamOut.flush();
} catch (UnknownHostException uhe) {
System.out.println("Host unknown: " + uhe.getMessage());
} catch (IOException ioe) {
System.out.println("Unexpected exception: " + ioe.getMessage());
}
String line = "";
while (!line.equals(".bye")) {
try {
line = console.readLine();
streamOut.writeUTF(myName + " <" + InetAddress.getLocalHost() + "> : " + line);
streamOut.flush();
} catch (IOException ioe) {
System.out.println("Sending error: " + ioe.getMessage());
}
}
}
public void stop() {
try {
if (console != null) console.close();
if (streamOut != null) streamOut.close();
if (socket != null) socket.close();
} catch (IOException ioe) {
System.out.println("Error closing ...");
}
}
public static void main(String args[]) {
ChatClient client = null;
if (args.length != 2)
System.out.println("Usage: java ChatClient host port");
else
client = new ChatClient(args[0], Integer.parseInt(args[1]));
}
}
ChatServer
import java.net.*;
import java.io.*;
import java.util.*;
public class ChatServer implements Runnable {
private ServerSocket server = null;
private Thread thread = null;
private ChatServerThread client = null;
private String clientSentence = null;
private int peers = 0;
private List clients = new ArrayList();
final List sockets = new ArrayList();
public ChatServer(int port) {
try {
System.out.println("Binding to port " + port + ", please wait ...");
server = new ServerSocket(port);
System.out.println("Server started: " + server);
start();
} catch (IOException ioe) {
System.out.println(ioe);
}
}
public void run() {
while (thread != null) {
try {
System.out.println("Waiting for a client ...");
addThread(server.accept());
} catch (IOException ie) {
System.out.println("Acceptance Error: " + ie);
}
}
}
public void addThread(Socket socket) {
System.out.println("Client accepted: " + socket);
client = new ChatServerThread(this, socket);
try {
client.open();
client.start();
} catch (IOException ioe) {
System.out.println("Error opening thread: " + ioe);
}
}
public void start() {
if (thread == null) {
thread = new Thread(this);
thread.start();
}
}
public void stop() {
if (thread != null) {
thread.stop();
thread = null;
}
}
public void increment(String sentence) {
peers++;
String[] info = sentence.split(" ");
String name = info[0].replace(":", "");
System.out.println(name + " Has joined the room, we now have " + peers + " peer(s).");
clients.add(name);
}
public Boolean isAllowed(String name, Socket socket) {
try {
String stringSearch = name;
BufferedReader bf = new BufferedReader(new FileReader("allowed.txt"));
int linecount = 0;
String line = "";
System.out.println("Searching for " + stringSearch + " in file...");
while ((line = bf.readLine()) != null) {
linecount++;
String[] words = line.split(" ");
for (String word : words) {
if (word.equals(stringSearch)) {
System.out.println("User is allowed");
registerSocket(socket);
return true;
}
}
}
bf.close();
} catch (IOException e) {
System.out.println("IO Error Occurred: " + e.toString());
}
System.out.println("User is not allowed");
return false;
}
public void showAll() {
for (int i = 0; i < clients.size(); i++) {
System.out.print(clients.get(i));
}
}
public void registerSocket(Socket socket) {
//socket = new DataOutputStream(socket.getOutputStream());
sockets.add(socket);
for (int i = 0; i < sockets.size(); i++) {
System.out.println(sockets.get(i));
}
}
public static void main(String args[]) {
ChatServer server = null;
if (args.length != 1)
System.out.println("Usage: java ChatServer port");
else
server = new ChatServer(Integer.parseInt(args[0]));
}
}
ChatServerThread
import java.net.*;
import java.io.*;
public class ChatServerThread extends Thread {
private Socket socket = null;
private ChatServer server = null;
private int ID = -1;
private DataInputStream streamIn = null;
private String clientSentence = null;
public String newGuy = null;
DataOutputStream streamOut = null;
public ChatServerThread(ChatServer _server, Socket _socket) {
server = _server;
socket = _socket;
ID = socket.getPort();
}
public void run() {
System.out.println("Server Thread " + ID + " running.");
while (true) {
try {
String sentence = streamIn.readUTF();
//System.out.println(sentence);
char c = sentence.charAt(0);
String[] command = null;
command = sentence.split(" ");
String name = command[0].substring(1);
System.out.println("Sending out: " + sentence + " via ");
streamOut.writeBytes(sentence);
if (c == ':') {
if (server.isAllowed(name, socket))
server.increment(sentence);
else {
close();
}
}
} catch (IOException ioe) {
}
}
}
public void open() throws IOException {
streamIn = new DataInputStream(new BufferedInputStream(socket.getInputStream()));
}
public void close() throws IOException {
if (socket != null) socket.close();
if (streamIn != null) streamIn.close();
}
}
