public static void main(String[] args) throws Exception {
        ExecutorService executor = Executors.newCachedThreadPool();

        for (int i = 0; i < 20; i++) { //200 hundred times will be called
            executor.submit(new Runnable() {
                public void run() {
                    Connectionn.getInstance().connect();
                }
            });
        }

        executor.shutdown();
        executor.awaitTermination(1, TimeUnit.DAYS);
    }