package Xwxx;

public class Person {

private String name;

private int age;

public Person() {

}

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 + "]";

}

}

package Xwxx;

public class Student extends Person{

private String name;

private int age;

public Student(){

}

public Student(String name, int age) {

this.name=name;

this.age=age;

}

@Override

public String toString() {

return "Student [name=" + name + ", age=" + age + "]";

}

}

package Xwxx;

import java.util.ArrayList;

import java.util.Collection;

import java.util.Iterator;

public class Test {

public static void main(String[] args) {

ArrayList list=new ArrayList();

list.add(new Person("zhangsan",28));

list.add(new Person("lisi",18));

printCollection(list);

ArrayList l=new ArrayList();

l.add(new Student("小明",22));

l.add(new Student("小红",20));

printCollection(l);

}

public static void printCollection(Collection> list){

//变成了object类了，所以只能访问object的方法

//？ extends Person是接收Person和其子类

//？ super Student是接收Student和其父类

Iterator> it=list.iterator();

while(it.hasNext()){

System.out.println(it.next());

}

}

}