import java.util.ArrayList;
import java.util.List;
/*
* 去除ArrayList集合中的重复元素。
*/
public class Test3 {
public static void main(String[] args) {
ArrayList list = new ArrayList();
list.add("诸葛亮");
list.add("诸葛亮");
list.add("黄盖");
list.add("张辽");
list.add("刘备");
List method = method(list);
System.out.println(method);
ArrayList list2 = new ArrayList();
list2.add(new Person("诸葛亮",100));
list2.add(new Person("诸葛亮",100));
list2.add(new Person("刘备",200));
list2.add(new Person("张辽",300));
list2.add(new Person("夏侯惇",400));
List method2 = method2(list2);
System.out.println(method2);
}
public static List method(ArrayList list) {
ArrayList newList = new ArrayList();
//遍历老集合
for (Object object : list) {
String name = (String)object;
//判断,如果这个元素在新集合中已经存在,则不添加。如果不存在就添加
if(!newList.contains(name)) {
newList.add(name);
}
}
return newList;
}
public static List method2(ArrayList list) {
ArrayList newList = new ArrayList();
//遍历老集合
for (Object object : list) {
Person person = (Person)object;
//判断,如果这个元素在新集合中已经存在,则不添加。如果不存在就添加
if(!newList.contains(person)) {
newList.add(person);
}
}
return newList;
}
}
|
|