这道题目的答案是不是有问题啊具体的题目是这样的:Consider the following java code: //

这道题目的答案是不是有问题啊
具体的题目是这样的:
Consider the following java code:
//in file Book.java
package com.bookstore;
public class Book
{
private String isbn;
public Book(){ isbn = "UNDEFINED_BOOK"; }
public String getIsbn(){ return isbn; }
public void setIsbn(String value){ this.isbn = value; }
}
//in file MusicCD.java
package com.bookstore;
public class MusicCD
{
private String isbn;
public MusicCD(){ isbn = "UNDEFINED_CD"; }
public String getIsbn(){ return isbn; }
public void setIsbn(String value){ this.isbn = value; }
}
Code for browse.jsp:


What is printed in the generated response of browse.jsp?
Select 1 correct option.
a.UNDEFINED_BOOK
b.UNDEFINED_CD
c.It will not compile
d.It will compile but will give an exception at request time.
它的答案说是选C 说不会通过编译的 可是我个人感觉应该是选D的 会通过编译只是会抛出ClassCastException的 大家都怎么认为啊? 高手能否为我讲解一下 谢谢啊!
可是这两个CLASS之间没有任何 关系啊～～～