工作日记-5 去除list里的重复元素

public List removeDeuplicate(List arlList)
{
HashSet h=new HashSet(arlList);
arlList.clear();
arlList.addAll(h);

List list=new ArrayList();
list=arlList;
return list;
}

private List<String> removeDuplicate(List<String> list)
{
List<String> result = new ArrayList<String>();

for (String s : list)
{
if (Collections.frequency(result, s) < 1)
result.add(s);
}

return result;
}