如何删除ArrayList中的重复值？

Question

现在：

我想要：

代码：

String[] contact = new String[contact_phoneList.size()];
for (int i = 0; i < contact_phoneList.size(); i++) {
    contact [i] = contact_phoneList.get(i);
}

Answer 1

使用HashSet删除重复的值：

HashSet hs = new HashSet();
hs.addAll(contact_phoneList); // name of contact_phoneList from which you want to remove duplicates 
contact_phoneList.clear();
contact_phoneList.addAll(hs);

不需要for循环