create a thread that handles multiple client connection

private static final int THREAD_POOL_SIZE = 10;

private static class ConnectionHandler implements Runnable {
    Socket socket;
    public ConnectionHandler(Socket socket) {
        this.socket = socket;
    }

    @Override
    public void run() {
        // handle request
    }
}

public static void main(String[] args) throws IOException {
    ServerSocket serverSocket = new ServerSocket(9090);
    while (true) {
        final Socket socket = serverSocket.accept();
        Thread t = new Thread(new ConnectionHandler(socket));
        t.start();
    }
}