public static void main(String[] args) {
        // Lock
        final ReentrantLock lock = new ReentrantLock();
        // 
        final Condition countCompleted = lock.newCondition();
        
        //Thread to wake up the condition
        Thread thread = new Thread(new Runnable() {
            public void run() {
                int i = 0;
                while (i < 5) {
                    System.out.println("Counting " + i + "...");
                    try {
                        Thread.sleep(1000);
                    } catch (InterruptedException e) {
                    }
                    i++;
                }
                // Locking is require before condition gets called
                lock.lock();
                // Wake up after 5 sec
                countCompleted.signal();
                lock.unlock();
            }
        });
        thread.start();
        
        // Locking is require before condition goes into sleep
        lock.lock();
        try {
            System.out.println("Start to wait...");
            // Sleep until condition is called
            countCompleted.await();
            System.out.println("Finished waiting.");
        } catch (InterruptedException e) {
        } finally {
            lock.unlock();
        }
    }

}