两种方式实现对Collection接口的集合遍历

我们有两种方法实现集合的遍历，第一种就是使用Iterator迭代器，第二种就是使用增强for循环，实际上增强for循环的底层逻辑还是使用iterator迭代器，使用断点debug一下即可。当我们使用terator迭代器的时候步骤如下：

(1)使用while（iterator.hasNext（））判断是否遍历完毕

(2)使用iterator.next（）实现遍历

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

public class test {
    @SuppressWarnings({"all"})
    public static void main(String[] args) {

        Collection list = new ArrayList();
        list.add(new Book("三国","罗贯中",22.0));
        list.add(new Book("西游记","吴承恩",36.3));

        Iterator iterator = list.iterator();//迭代器
        
        //One
        while (iterator.hasNext()) {
            Object obj =  iterator.next();
            System.out.println(obj);

        }
        System.out.println("==============");
        //Two
        for(Object obj1: list){
            System.out.println(obj1);
        }

    }
}

class Book{
    private String name;
    private String author;
    private double price;

    public Book(String name, String author, double price) {
        this.name = name;
        this.author = author;
        this.price = price;
    }

    public String getName() {
        return name;
    }

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

    public String getAuthor() {
        return author;
    }

    public void setAuthor(String author) {
        this.author = author;
    }

    public double getPrice() {
        return price;
    }

    public void setPrice(double price) {
        this.price = price;
    }

    @Override
    public String toString() {
        return "Book{" +
                "name='" + name + '\'' +
                ", author='" + author + '\'' +
                ", price=" + price +
                '}';
    }
}