Initial chat room

src/main/java/org/example/ServerApp.java

@@ -0,0 +1,92 @@
+package org.example;
+
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.InputStreamReader;
+import java.io.PrintWriter;
+import java.net.ServerSocket;
+import java.net.Socket;
+import java.util.ArrayList;
+import java.util.List;
+
+public class ServerApp {
+    private static final int PORT = 1234;
+    private List<ClientHandler> clients;
+
+    public ServerApp() {
+        clients = new ArrayList<>();
+    }
+
+    public void start() {
+        try {
+            ServerSocket serverSocket = new ServerSocket(PORT);
+            System.out.println("Server started on port " + PORT);
+
+            while (true) {
+                Socket clientSocket = serverSocket.accept();
+                System.out.println("New client connected: " + clientSocket);
+
+                ClientHandler clientHandler = new ClientHandler(clientSocket);
+                clients.add(clientHandler);
+                clientHandler.start();
+            }
+        } catch (IOException e) {
+            e.printStackTrace();
+        }
+    }
+
+    private void broadcastMessage(String message, ClientHandler sender) {
+        for (ClientHandler client : clients) {
+            if (client != sender) {
+                client.sendMessage(message);
+            }
+        }
+    }
+
+    private void removeClient(ClientHandler client) {
+        clients.remove(client);
+    }
+
+    private class ClientHandler extends Thread {
+        private Socket clientSocket;
+        private BufferedReader in;
+        private PrintWriter out;
+
+        public ClientHandler(Socket socket) {
+            this.clientSocket = socket;
+        }
+
+        @Override
+        public void run() {
+            try {
+                in = new BufferedReader(new InputStreamReader(clientSocket.getInputStream()));
+                out = new PrintWriter(clientSocket.getOutputStream(), true);
+
+                String clientMessage;
+                while ((clientMessage = in.readLine()) != null) {
+                    broadcastMessage(clientMessage, this);
+                }
+            } catch (IOException e) {
+                e.printStackTrace();
+            } finally {
+                try {
+                    in.close();
+                    out.close();
+                    clientSocket.close();
+                    removeClient(this);
+                } catch (IOException e) {
+                    e.printStackTrace();
+                }
+            }
+        }
+
+        public void sendMessage(String message) {
+            out.println(message);
+        }
+    }
+
+    public static void main(String[] args) {
+        ServerApp server = new ServerApp();
+        server.start();
+    }
+}