java map 自定义类型函数调用?

Question

import java.util.*;class student {String name;int score;student(String name,int score){this.name=name;this.score=score;}void shuchu(){System.out.println(name+" "+score);}}public class banji_1{public static void main(String ag[]){Map aa=new TreeMap();aa.put(0,new student("a",1));aa.put(1,new student("b",2));aa.put(2,new student("c",3));for(int i=0;i<4;i++){aa.get(i).shuchu();}}}编译报错

Answer 1

aa.get(i).shuchu();改成((student)aa.get(i)).shuchu();
get()返回的是Object类型需要强制转换成你需要的对象类型
或者在Map声明时就规定泛型

Answer 2

将for语句改变成下面的就可以了
for(int i=0;i<3;i++)
{

((student) aa.get(i)).shuchu();

}