Java基础-集合Collection遍历的方式

package com.hspedu.collection_;


import java.util.ArrayList;
import java.util.Collection;
import java.util.Iterator;

@SuppressWarnings({"all"})
public class Course501 {
    public static void main(String[] args) {
        // 遍历集合Collection元素对象的方法


        Collection collection = new ArrayList();
        collection.add(new Cat("小白", 3));
        collection.add(new Cat("小黑", 5));
        collection.add(new Cat("小花", 2));
        collection.add("Tom");
        collection.add("Mary");
        collection.add(100);
        collection.add(200);

        //  1、迭代器iterator：先指向集合第一个元素对象前 -> 依次往下遍历
        Iterator iterator = collection.iterator();
        while (iterator.hasNext()) {
            Object next = iterator.next();
            System.out.println("next = " + next);
        }
        System.out.println("=============================");

        // 2、增强for循环：底层同样是迭代器
        for (Object object : collection) {
            System.out.println("object = " + object);
        }
    }
}


class Cat {
    private String name;
    private int age;

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

    @Override
    public String toString() {
        return "Cat{" +
                "name='" + name + '\'' +
                ", age=" + age +
                '}';
    }
}