The program starts two threads, t1 and t2. The first thread (t1) increments and prints the volatile integer x variable until it is less than 3, while the second thread (t2) increments and prints the AtomicInteger xObj until it is less than 3. Since both increment and print their respective values independently, their outputs can interleave in any order, thus, the program prints t1: 1: t2 : 1: t1 : 2 : t2 : 2: in random order.