集合遍历之迭代器遍历。

package com.heima.collection;

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

import com.heima.bean.Student;

public class Demo04 {
/*
* 迭代器 集合是用来存储元素，存储的元素需要查看，那么就需要迭代(遍历)
*/
public static void main(String[] args) {
// test01();
Collection c = new ArrayList();
c.add(new Student("王五", 23));
c.add(new Student("列斯", 43));
c.add(new Student("赵六", 63));
c.add(new Student("王麻子", 23));
Iterator<Student> it = c.iterator();
while (it.hasNext()) {
System.out.println(it.next());
}
}

private static void test01() {
Collection c = new ArrayList();
c.add("a");
c.add("a1");
c.add("a2");
c.add("a3");
c.add("a4");
Iterator it = c.iterator();// 获取迭代器
while (it.hasNext()) {
System.out.println(it.next());
}
// boolean b = it.hasNext();//判断集合中是否有元素
// Object o = it.next();//获取集合中的元素
}
}