JAVA小练习118——HashMap

import java.util.HashMap;
class Person{
	
	int id;
	String name;
	
	public Person(int id, String name) {
		super();
		this.id = id;
		this.name = name;
	}

	@Override
	public String toString() {
		return "{编号："+this.id+"姓名："+this.name+"}";
	}

	@Override
	public int hashCode() {
		return this.id;
	}

	@Override
	public boolean equals(Object obj) {
		Person p=(Person) obj;
		return this.id==p.id;
	}

		
}


public class Demo118 {

	public static void main(String[] args) {
		HashMap<Person,String> map=new HashMap<Person,String>();
		map.put(new Person(110,"狗娃"),"001");
		map.put(new Person(120,"狗三"),"002");
		map.put(new Person(130,"狗子"),"003");
		//如果身份证编号一致，则被视为重复元素，不允许添加
		map.put(new Person(130,"宝宝"),"007");//返回值为0，重复元素，舍弃。但是相同键的值会取代原来的值，即003---007
		System.out.println(map);
		

	}

}