集合的嵌套遍历

Posted 2021-02-07 zuixinxian

package com.yjf.esupplier.common.test;

import com.yjf.common.util.ToString;

import java.util.ArrayList;

/**
 * @author shusheng
 * @description  集合的嵌套遍历
 * @Email [email protected]
 * @date 2018/12/13 17:54
 */
public class ArrayListDemo {

    public static void main(String[] args) {
        // 创建大集合
        ArrayList<ArrayList<Student>> bigArrayList = new ArrayList<ArrayList<Student>>();
        // 创建第一个班级的学生集合
        ArrayList<Student> firstArrayList = new ArrayList<Student>();
        //创建学生
        Student s1 = new Student("唐僧", 31);
        Student s2 = new Student("孙悟空", 30);
        Student s3 = new Student("猪八戒", 29);
        Student s4 = new Student("沙僧", 28);
        Student s5 = new Student("白龙马", 27);
        // 学生进班
        firstArrayList.add(s1);
        firstArrayList.add(s2);
        firstArrayList.add(s3);
        firstArrayList.add(s4);
        firstArrayList.add(s5);
        // 把第一个班级存储到学生系统中
        bigArrayList.add(firstArrayList);

        // 创建第二个班级的学生集合
        ArrayList<Student> secondArrayList = new ArrayList<Student>();
        // 创建学生
        Student s11 = new Student("诸葛亮", 31);
        Student s22 = new Student("司马懿", 32);
        Student s33 = new Student("周瑜", 33);
        // 学生进班
        secondArrayList.add(s11);
        secondArrayList.add(s22);
        secondArrayList.add(s33);
        // 把第二个班级存储到学生系统中
        bigArrayList.add(secondArrayList);

        // 创建第三个班级的学生集合
        ArrayList<Student> thirdArrayList = new ArrayList<Student>();
        // 创建学生
        Student s111 = new Student("宋江", 44);
        Student s222 = new Student("吴用", 43);
        Student s333 = new Student("高俅", 42);
        Student s444 = new Student("李师师", 41);
        // 学生进班
        thirdArrayList.add(s111);
        thirdArrayList.add(s222);
        thirdArrayList.add(s333);
        thirdArrayList.add(s444);
        // 把第三个班级存储到学生系统中
        bigArrayList.add(thirdArrayList);

        // 遍历集合
        for (ArrayList<Student> array : bigArrayList) {
            for (Student s : array) {
                System.out.println(s.getName() + "---" + s.getAge());
            }
        }

    }

}

class Student {

    private String name;
    private int age;

    public Student(String name, int age) {
        this.name=name;
        this.age=age;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public Integer getAge() {
        return age;
    }

    public void setAge(Integer age) {
        this.age = age;
    }

    @Override
    public String toString() {
        return ToString.toString(this);
    }
}