Java常用技巧

1. List转换为Set

List<String> list = new ArrayList<String>();
list.add("Hello");
list.add("World");
list.add("World");
Set<String> set = new HashSet<String>();
set.addAll(list);
Iterator<String> ite = set.iterator();
while(ite.hasNext()) {
  System.out.println(ite.next());
}