複製代碼代碼如下:
class ArrayListTest1 {
public static void main(String[] args) {
ArrayList al = new ArrayList();
al.add("java03");
al.add("java03");
al.add("java01");
al.add("java02");
al.add("java01");
al.add("java02");
al.add("java01");
System.out.println(al);
al = singleElement(al);
System.out.println(al);
}
//返回List合適些
public static ArrayList singleElement(ArrayList al){
//定義一個臨時容器
ArrayList newAl = new ArrayList();
//在迭代是循環中next調用一次，就要hasNext判斷一次
Iterator it = al.iterator();
while (it.hasNext()){
Object obj = it.next();//next()最好調用一次就hasNext()判斷一次否則容易發生異常
if (!newAl.contains(obj))
newAl.add(obj);
}
return newAl;
}
}