static void main(String[] args) throws InterruptedException { // Thread f1: waits for i to change from 0 Thread t1 = new Thread(() -> { int local; while ((local = i.get()) == 0) { // Busy-wait (spinlock) } System.out.printf("i's value has changed to %d.%n", local); });

// Thread f2: changes i after 10 seconds Thread t2 = new Thread(() -> { int local = 99; try { Thread.sleep(10_000); // sleep 10 seconds