What is the correct way to iterate over a HashSet?

for (int i = 0; i < hashSet.size(); i++) {
    System.out.println(hashSet.get(i));
}

Iterator<String> it = hashSet.iterator();
while (it.hasNext()) {
    System.out.println(it.next());
}

for (String item : hashSet) {
    System.out.println(item);
}