How to use CountDownLatch ?

Using CountDownLatch

// Initialize latch with counter
final CountDownLatch latch = new CountDownLatch(5);

// Keep the latch waiting for all 5 activities to be done
try {
    latch.await(); } catch (InterruptedException ignored) { 
}


// Run the individual task (activity) and decrement the counter
try {
    // task.run();
} finally {
    latch.countDown();
}