buybook.java

从一开始就使用动态提交技术

package bookshop;

import java.io.*;
import java.util.*;

public class BuyBook implements Serializable
{
	Hashtable Books=new Hashtable();
	public void BuyBook()
	{}
	public void addBook(String bookId,int bookNumber)
	{
		if(Books.containsKey(bookId))
		{
			int tempNumber=((Integer)Books.get(bookId)).intValue();
			tempNumber=tempNumber+bookNumber;
			Books.put(bookId,new Integer(tempNumber));
		}
		else
		{
			Books.put(bookId,new Integer(bookNumber));
		}
	}
	public void modifyBook(String bookId,int bookNumber)
	{
		
		Books.put(bookId,new Integer(bookNumber));
		
	}
	public void delBook(String bookId)
	{
		if(Books.containsKey(bookId))
		{
			Books.remove(bookId);
		}
	}
	public Hashtable listBooks()
	{
		return Books;
	}
}