300.22HashSet中添加三个Person对象

import java.util.*;public class T1 {public static void main(String[] args) {HashSet hs = new HashSet();Person p1  = new Person("gyc",20);Person p2  = new Person("gyf",21);Person p3  = new Person("gjq",25);Person p4  = new Person("gyc",20);hs.add(p1);hs.add(p2);hs.add(p3);hs.add(p4);Iterator it = hs.iterator();while(it.hasNext()) {System.out.println(it.next());}}}class Person{String name;int age;Person(){}Person(String name,int age){this.name = name;this.age = age;}public String toString() {return "name:"+name+"  age:"+age;}public int hashCode() {return name.hashCode();}public boolean equals(Object o) {if(this == o)return true;if (o instanceof Person) {Person p = (Person)o;if(this.name.equals(((Person) o).name)&&this.age == ((Person)o).age) {return true;}}return false;}}