java 16

  集合的嵌套遍历
  需求:
    自然界有很多动物的种类,猫科,犬科,鸟类这些。
    那就是有很多的ArrayList<Animal>
    而现在,我想要把这些ArrayList<Animal>也用集合存储,怎么办呢?
  那就使用集合的嵌套使用:
    就是这个样子的:ArrayList< ArrayList<Animal> >

动物类:

 1 package cn_JDK5new;
 2 
 3 public class Animal {
 4         
 5         private String name;
 6         private String color;
 7         private int age;
 8         
 9         
10         
11         public Animal() {
12             super();
13             // TODO Auto-generated constructor stub
14         }
15         
16         
17         
18         public Animal(String name, String color, int age) {
19             super();
20             this.name = name;
21             this.color = color;
22             this.age = age;
23         }
24         
25         
26         public String getName() {
27             return name;
28         }
29         public void setName(String name) {
30             this.name = name;
31         }
32         public String getColor() {
33             return color;
34         }
35         public void setColor(String color) {
36             this.color = color;
37         }
38         public int getAge() {
39             return age;
40         }
41         public void setAge(int age) {
42             this.age = age;
43         }
44         
45         
46 }

测试类:

 1 package cn_JDK5new;
 2 
 3 import java.util.ArrayList;
 4 
 5 import zl_ObjectTest1.Animal;
 6 
 7 public class BigAnimalTest {
 8 
 9 public static void main(String[] args) {
10 //创建集合1
11 ArrayList<Animal> list1 = new ArrayList<Animal>();
12 
13 //猫科
14 Animal a1 = new Animal("短尾猫","白色",1);
15 Animal a2 = new Animal("加菲猫","黄色",3);
16 Animal a3 = new Animal("波斯猫","黑色",2);
17 
18 //添加进到集合1
19 list1.add(a1);
20 list1.add(a2);
21 list1.add(a3);
22 
23 //创建集合2
24 ArrayList<Animal> list2 = new ArrayList<Animal>();
25 
26 //犬科
27 Animal a4 = new Animal("哈士奇","白色",1);
28 Animal a5 = new Animal("萨摩耶","纯白",2);
29 Animal a6 = new Animal("中华田园犬","黑色",2);
30 Animal a7 = new Animal("腊肠犬","黄色",3);
31 Animal a8 = new Animal("泰迪","纯白",2);
32 
33 //添加进集合2
34 list2.add(a4);
35 list2.add(a5);
36 list2.add(a6);
37 list2.add(a7);
38 list2.add(a8);
39 
40 
41 //创建集合3
42 ArrayList<Animal> list3 = new ArrayList<Animal>();
43 
44 //鸟类
45 Animal a9 = new Animal("鸽子","白色",1);
46 Animal a10 = new Animal("老鹰","黑色",2);
47 
48 //添加进集合3
49 list3.add(a9);
50 list3.add(a10);
51 
52 
53 //创建总的集合
54 ArrayList<ArrayList<Animal>> bigAnimal = new ArrayList<ArrayList<Animal>>();
55 //把这些集合都放进总集合中
56 bigAnimal.add(list1);
57 bigAnimal.add(list2);
58 bigAnimal.add(list3);
59 
60 //进行总集合的遍历
61 for(ArrayList<Animal> aa : bigAnimal){
62 
63 for(Animal a : aa){
64 
65 System.out.println(a.getName()+"	"+a.getColor()+"	"+a.getAge());
66 }
67 }
68 }
69 }
何事都只需坚持.. 难? 维熟尔。 LZL的自学历程...只需坚持
原文地址:https://www.cnblogs.com/LZL-student/p/5898578.html