LinkedList类的基本方法的用法

 1 package cn.zmh.LinkedList;
 2 
 3 import java.util.Iterator;
 4 import java.util.LinkedList;
 5 
 6 public class LinkendListDemo1 {
 7     public static void main(String[] args) {
 8         fun2();
 9         fun1_3();
10 
11 
12     }
13 
14     // 1  addFirst();从前面添加   addLast(); 从后面添加
15     public static void fun1() {
16         LinkedList<String> link = new LinkedList<>();
17         link.addFirst("钱");
18         link.addFirst("赵");
19         link.addLast("孙");
20         link.addLast("李");
21         Iterator<String> it = link.iterator();
22         while (it.hasNext()) {
23             String s = it.next();
24             System.out.println(s);
25         }
26     }
27     //  1_1  addFirst();从前面添加  getFirst();获取第一个元素
28     //  Iterator  迭代器
29     public static void fun1_1() {
30         LinkedList<String> link = new LinkedList<>();
31         link.addFirst("李白1");
32         link.addFirst("李白2");
33         link.addFirst("李白3");
34         //获取第一个集合元素（李白3）；
35         String first = link.getFirst();
36         System.out.println(first);
37         Iterator<String> it = link.iterator();
38         while (it.hasNext()) {
39             String s = it.next();
40             System.out.println(s);
41         }
42     }
43     // 1_2  集合转数组
44     public static void fun1_2() {
45         LinkedList<String> link = new LinkedList<>();
46         link.addFirst("a1");
47         link.addFirst("a2");
48         link.addFirst("a3");
49         System.out.println(link);
50         Object[] array = link.toArray();
51         //for循环
52         for (int i=0;i<array.length;i++){
53             System.out.println(array[i]);
54         }
55         //迭代器
56         Iterator<String> it = link.iterator();
57         while(it.hasNext()){
58             String s = it.next();
59             System.out.println(s);
60         }
61     }
62     public static void fun1_3(){
63         LinkedList<String> link = new LinkedList<>();
64         link.add("a1");
65         link.add("a2");
66         link.add("a3");
67         System.out.println(link);
68         //删除第一个
69         String rem = link.removeFirst();
70         //删除最后一个
71         String rem1 = link.removeLast();
72         System.out.println("被删除的："+rem+"	"+rem1);
73         System.out.println(link);
74     }
75     // 2  getFirst();获取第一个     getLast(); 获取最后一个
76     public static void fun2() {
77         LinkedList<String> link = new LinkedList<>();
78         link.add("张飞1");
79         link.add("刘备2");
80         link.add("关羽3");
81         //isEmpty()  判断集合是否为空  在进行操作
82         if (!link.isEmpty()) {
83             String first = link.getFirst();
84             System.out.println(first);
85         }
86     }
87     //  3  removeFirst(); removeLast();删除功能
88     public static void fun3() {
89         LinkedList<String> link = new LinkedList<>();
90         link.add("每当我听到雨声");
91         link.add("就行听到了心中的迷茫");
92         String s = link.removeFirst();
93         System.out.println("被删除的：" + s);
94         System.out.println(link);
95     }
96 }