【Java學習筆記】<集合框架>定義功能去除ArrayList中的重復元素，學習筆記arraylist

【Java學習筆記】<集合框架>定義功能去除ArrayList中的重復元素，學習筆記arraylist

 1 import java.util.ArrayList;
 2 import java.util.Iterator;
 3 
 4 import cn.itcast.p1.bean.Person;
 5 
 6 public class ArrayListTest2 {
 7 
 8     public static void main(String[] args) {
 9         
10         ArrayList al = new ArrayList();
11         
12         al.add(new Person("lisi1",21));
13         al.add(new Person("lisi2",22));  //與28行的Person，內容相同，地址不同
14         al.add(new Person("lisi3",23));
15         al.add(new Person("lisi4",24));
16         al.add(new Person("lisi2",22));
17         al.add(new Person("lisi3",23));
18         
19         System.out.println(al);
20         
21         al = getSingleElement(al);   //去除重復方法
22         
23         System.out.println(al);
24         
25         System.out.println(al.remove(new Person("lisi2",22)));//remove內部是用equals來判斷刪除內容
26         System.out.println(al);
27 
28     }
29 
30 
31     private static ArrayList getSingleElement(ArrayList al) {
32         ArrayList temp = new ArrayList();
33         
34         Iterator it = al.iterator();
35         
36         while (it.hasNext())
37         {
38             Object obj = it.next();
39             
40             if (!temp.contains(obj))
41             {
42                 temp.add(obj);
43             }
44         }
45         
46         return temp;
47     }
48 
49 }