RR-another version

import java.io.*;
import java.net.*;
import java.util.LinkedList;

public class RoundRobin {
    private static LinkedList<Socket> servers = new LinkedList<>();
    private static int serverIndex = 0;
    
    public static void main(String[] args) {
        try {
            servers.add(new Socket("127.0.0.1", 12345));
            servers.add(new Socket("127.0.0.1", 5000));
            servers.add(new Socket("127.0.0.1", 4040));
            
            ServerSocket serverSocket = new ServerSocket(5500);
            
            while (true) {
                Socket conn = serverSocket.accept();
                Socket selected = getNextServer();
                processRequest(conn, selected);
            }
            
        } catch (IOException e) {
            System.err.println(e.getMessage());
        } finally {
            closeConnections();
        }
    }
    
    private static synchronized Socket getNextServer() {
        serverIndex = (serverIndex + 1) % servers.size();
        return servers.get(serverIndex);
    }
    
    private static void processRequest(Socket client, Socket server) throws IOException {
        try {
            InputStream in = client.getInputStream();
            OutputStream out = client.getOutputStream();
            DataInputStream din = new DataInputStream(in);
            DataOutputStream dout = new DataOutputStream(server.getOutputStream());
            
            // Read data from client and send it to server
            byte[] buffer = new byte[1024];
            int bytesRead;
            while ((bytesRead = in.read(buffer)) != -1) {
                dout.write(buffer, 0, bytesRead);
                dout.flush();
            }
            
            // Read response from server and send it back to client
            buffer = new byte[1024];
            bytesRead = server.getInputStream().read(buffer);
            if (bytesRead > 0) {
                out.write(buffer, 0, bytesRead);
                out.flush();
            }
            
        } finally {
            client.close();
        }
    }
    
    private static void closeConnections() {
        try {
            for (Socket server : servers) {
                server.close();
            }
        } catch (IOException e) {
            System.err.println(e.getMessage());
        }
    }
}