List集合联系

创建一个List,在List 中增加三个工人,基本信息如下:

姓名 年龄 工资

zhang3 18 3000

li4 25 3500

wang5 22 3200

a) li4 之前插入一个工人,信息为:姓名:zhao6,年龄:24,工资3300

b) 删除wang5 的信息

c) 利用for 循环遍历,打印List 中所有工人的信息

d) 判断是否存在liudehua,存在输出Y,否则输出N

e) 利用迭代遍历,对List 中所有的工人调用work 方法。

工人类

 1 package com.lanxi.demo1_1;
 2 public class Worker {
 3     private String name;
 4     private int age;
 5     private int sal;
 6     @Override//重写toString方法
 7     public String toString() {
 8         return "Worker [name=" + name + ", age=" + age + ", sal=" + sal + "]";
 9     }
10     public Worker() {//无参构造方法
11         super();
12     }
13     public Worker(String name, int age, int sal) {//有参构造方法
14         super();
15         this.name = name;
16         this.age = age;
17         this.sal = sal;
18     }
19     //getter,setter方法
20     public String getName() {
21         return name;
22     }
23     public int getAge() {
24         return age;
25     }
26     public int getSal() {
27         return sal;
28     }
29 }

测试类

 1 package com.lanxi.demo1_1;
 2 import java.util.Iterator;
 3 import java.util.LinkedList;
 4 import java.util.List;
 5 public class Test {
 6     public static void main(String[] args) {
 7         List list=new LinkedList();
 8         Worker work1=new Worker("zhang3",18,3000);
 9         Worker work2=new Worker("li4",25,3500);
10         Worker work3=new Worker("wang5",22,3200);
11         //将对象放入集合
12         list.add(work1);
13         list.add(work2);
14         list.add(work3);
15         list.add(1, new Worker("zhao6",24,3300));        //在li4前插入一个工人
16         list.remove(work3);//删除wang5的信息
17         for (int i = 0; i < list.size(); i++) {//for循环遍历
18             System.out.println(list.get(i));
19         }
20         System.out.println();
21         //判断liudehua是否存在,并遍历循环中所有元素
22         Iterator it=list.iterator();
23         while(it.hasNext()){
24             Worker wo=(Worker)it.next();
25             if("liudehua".equals(wo.getName())){
26                 System.out.println(wo);
27                 System.out.println("it is find liudehua");
28                 break;
29             }else{
30                 System.out.println(wo);
31                 System.out.println("no find liudehua");
32                 break;
33             }
34         }
35     }
36 
37 }

测试结果截屏

原文地址:https://www.cnblogs.com/www-x/p/8666696.html