public static void before() { Set set = new TreeSet(); set.add("2"); set.add(3); set.add("1"); Iterator it = set.iterator(); while (it.hasNext()) System.out.print(it.next() + " "); }
The before() method will print 1 2
The before() method will print 1 2 3
The before() method will print three numbers, but the order cannot be determined
The before() method will not compile
The before() method will throw an exception at runtime