Java 往hashSet集合中存入自定义对象

姓名和年龄相同为同一个人，重复元素。

import java.util.*;
class HashSetTest 
{
  public static void sop(Object obj)
  {
    System.out.println(obj);
  }
  public static void main(String[] args) 
  {
    HashSet hs = new HashSet();

    hs.add(new Person("a1",11));
    hs.add(new Person("a2",12));
    hs.add(new Person("a3",13));
//    hs.add(new Person("a2",12));
//    hs.add(new Person("a4",14));

    //sop("a1:"+hs.contains(new Person("a2",12)));
      
//    hs.remove(new Person("a4",13));   

    Iterator it = hs.iterator();
    while(it.hasNext())
    {
      Person p = (Person)it.next();
      sop(p.getName()+"::"+p.getAge());
    }
  }
}
class Person
{
  private String name;
  private int age;
  Person(String name,int age)
  {
    this.name = name;
    this.age = age;
  }  
  public int hashCode()
  {
    System.out.println(this.name+"....hashCode");
    return name.hashCode()+age*37;
  }
  public boolean equals(Object obj)
  {
    if(!(obj instanceof Person))
      return false;
    Person p = (Person)obj;
    System.out.println(this.name+"...equals.."+p.name);
    return this.name.equals(p.name) && this.age == p.age;
  }  
  public String getName()
  {
    return name;
  }
  public int getAge()
  {
    return age;
  }
}