package com.loaderman.list; import java.util.ArrayList; import com.loaderman.bean.Person; public class Demo_ArrayListArrayList { /** * * A:案例演示 * 集合嵌套之ArrayList嵌套ArrayList * 案例: * 我们学科,学科又分为若个班级 * 整个学科一个大集合 * 若干个班级分为每一个小集合 */ public static void main(String[] args) { ArrayList<ArrayList<Person>> list = new ArrayList<>(); ArrayList<Person> first = new ArrayList<>(); //创建第一个班级 first.add(new Person("杨幂", 30)); first.add(new Person("李冰冰", 33)); first.add(new Person("范冰冰", 20)); ArrayList<Person> second = new ArrayList<>(); second.add(new Person("黄晓明", 31)); second.add(new Person("赵薇", 33)); second.add(new Person("陈坤", 32)); //将班级添加到学科集合中 list.add(first); list.add(second); //遍历学科集合 for(ArrayList<Person> a : list) { for(Person p : a) { System.out.println(p); } } } }
package com.loaderman.bean; public class Person { private String name; private int age; public Person() { super(); } public Person(String name, int age) { super(); this.name = name; this.age = age; } public String getName() { return name; } public void setName(String name) { this.name = name; } public int getAge() { return age; } public void setAge(int age) { this.age = age; } @Override public String toString() { return "Person [name=" + name + ", age=" + age + "]"; } /*@Override public boolean equals(Object obj) { Person p = (Person)obj; return this.name.equals(p.name) && this.age == p.age; }*/ }