String[] x = new String[] {"Vat", "Bat", "Cat"};
Arrays.sort(x); // mutates x into Bat, Cat, Vat
Arrays.sort(x, Collections.reverseOrder()); // mutates x into Vat, Cat, Bat
Arrays.sort(x, 0, 2) // sorts the first two elements, leaving the rest unchanged (Cat, Vat, Bat)