JAVA配置环境好像出了问题：java高手看过来

coolseafy 2003-05-11 09:47:06

现在所有涉及到类引用的（我也不知道是不是该叫类引用）java文件都编译不过去了。
提示识别不了。举个例子：
现在我有两个类放在一个包内。
一个类是Book.java
package com.wrox.begjsp.model2;
public class Book
{
String ISBN;
String bookTitle;
float price;
int quantity;
public Book(){
ISBN="";
bookTitle="";
price=(float)0.0;
quantity=0;
}
public void setISBN(String ISBN){
this.ISBN=ISBN;
}
public String getISBN(){
return this.ISBN;
}
public void setBookTitle(String bookTitle){
this.bookTitle=bookTitle;
}
public String getBookTitle(){
return this.bookTitle;
}
public void setPrice(float price){
this.price=price;
}
public float getPrice(){
return this.price;
}
public void setQuantity(int quantity){
this.quantity=quantity;
}
public int getQuantity(){
return this.quantity;
}
};
一个类是ShoppingCart.java
package com.wrox.begjsp.model2;
import java.util.ArrayList;
import java.util.Iterator;

public class ShoppingCart{
private ArrayList items=new ArrayList();
public void addItem(Book b){
boolean foundBook=false;
if (items.size()==0){
items.add(b);
}else{
for (int i=0;i<items.size();i++){
Book book=(Book)items.get(i);
if (book.getISBN().equals(b.getISBN())){
book.setQuantity(book.getQuantity()+1);
foundBook=true;
break;
}
}
if (!foundBook){
items.add(b);
}
}
}

public Iterator getContents(){
System.out.println(items.size());
return items.iterator();
}
}
编译过Book.java后在编译ShoppingCart的时候，提示
C:\jakarta-tomcat-4.1.24\webapps\upload\WEB-INF\classes\com\wrox\begjsp\model2\ShoppingCart.java:7: cannot resolve symbol
symbol : class Book
location: class com.wrox.begjsp.model2.ShoppingCart
public void addItem(Book b){
^
C:\jakarta-tomcat-4.1.24\webapps\upload\WEB-INF\classes\com\wrox\begjsp\model2\ShoppingCart.java:13: cannot resolve symbol
symbol : class Book
location: class com.wrox.begjsp.model2.ShoppingCart
Book book=(Book)items.get(i);
^
C:\jakarta-tomcat-4.1.24\webapps\upload\WEB-INF\classes\com\wrox\begjsp\model2\ShoppingCart.java:13: cannot resolve symbol
symbol : class Book
location: class com.wrox.begjsp.model2.ShoppingCart
Book book=(Book)items.get(i);
^
3 errors

但是这个文件我以前编译过，成功编译而且原来编译出来的class文件我现在都可以用。
突然不行了。现在我试了一下，好像所有在一个类里使用另一个类的都不能编译了。

help!!!!!!

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