android List去掉重复数据

利用了Set不重复的特性

方法一：

public static List removeDuplicateWithOrder(List list) {
Set set = new HashSet();
List newList = new ArrayList();
for (Iterator iter = list.iterator(); iter.hasNext();) {
Object element = iter.next();
if (set.add(element))
newList.add(element);
}
return newList;
}

方法二：

public static List<String> removeDuplicate(List<String> list)
{
Set set = new LinkedHashSet<String>();
set.addAll(list);
list.clear();
list.addAll(set);
return list;
}

方法三：

import java.util.*;
class sigleE
{
public static void main(String[] args)
{
ArrayList al = new ArrayList();
al.add("java1");
al.add("java2");
al.add("java1");
al.add("java3");
System.out.println(al);
al = list(al);
System.out.println(al);
}
public static ArrayList list(ArrayList al)
{
ArrayList newal = new ArrayList();//新建一个中间集合
for(Iterator it = al.iterator();it.hasNext();)//集合循环
{
Object obj = it.next();
if(!newal.contains(obj))//不包含重复的输出
newal.add(obj);
}
return newal;
}
}