java中map使用非系统类作为key

需要覆写equals和hashCode方法

import java.util.Map ;
import java.util.HashMap ;
class Person{
	private String name ;
	private int age ;
	public Person(String name,int age){
		this.name = name ;
		this.age = age ;
	}
	public String toString(){
		return "姓名：" + this.name + "；年龄：" + this.age ;
	}
	public boolean equals(Object obj){
		if(this==obj){
			return true ;
		}
		if(!(obj instanceof Person)){
			return false ;
		}
		Person p = (Person)obj ;
		if(this.name.equals(p.name)&&this.age==p.age){
			return true ;
		}else{
			return false ;
		}
	}
	public int hashCode(){
		return this.name.hashCode() * this.age ;
	}
};
public class HashMapDemo08{
	public static void main(String args[]){
		Map<Person,String> map = null ;
		map = new HashMap<Person,String>() ;
		map.put(new Person("张三",30),"zhangsan");	// 增加内容
		System.out.println(map.get(new Person("张三",30))) ;
	}
};