bookdb.java

实现在线书店的基本功能 应用了hibernate+jsp 技术采用了mvc三层设计模式

package mypack;



import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.Iterator;

import java.util.List;
import java.util.logging.Level;
import java.util.logging.Logger;



import org.hibernate.Query;
import org.hibernate.Session;
import org.hibernate.cfg.Configuration;
import org.hibernate.SessionFactory;
import org.hibernate.Transaction;



/**
 * Hibernate Utility class with a convenient method to get 
Session Factory object.
 *
 * @author Administrator
 */
public class BookDB {
    private static final SessionFactory sessionFactory;
    

    static {
        try {
            // Create the SessionFactory from standard(hibernate.cfg.xml) 
            // config file.
            sessionFactory = new Configuration().configure
().buildSessionFactory();
        } catch (Throwable ex) {
            // Log the exception. 
            System.err.println("Initial SessionFactory creation failed." + ex);
            throw new ExceptionInInitializerError(ex);
        }
    }

    public static SessionFactory getSessionFactory() {
        return sessionFactory;
    }
    public int getNumberOfBooks()
    {
        ArrayList books=new ArrayList();
        Query q=getOpenSession().createQuery("from BookDetails");
        books=(ArrayList)q.list();
        return books.size();
    }
    public Collection getBooks()
    {   
       
        Query q=getOpenSession().createQuery("from BookDetails");
        List list=q.list();
        return list;
        
        
    }
    
   
    public BookDetails getBookDetails(String bookId)
    {
          BookDetails bd=null;
        try{
               bd=(BookDetails)getOpenSession().load(BookDetails.class, bookId);
        }catch(Exception e)
        {
            return null;
        }
        if(bd!=null)
            return  bd;
        else
            return null;
    
        
    }
    public BookDetails getBookByTitle(String title)
    {
          BookDetails bd=null;
      try {
         Session s=getOpenSession();
          Query query=s.createQuery("from BookDetails as bd where bd.title like:title");
          query.setString("title", title);
          bd=(BookDetails)query.uniqueResult();
          s.close();
         } catch (Exception e) {
          }
          if(bd!=null)
              return bd;
          else
              return null;
        
       
        
    }
     public BookDetails getBookByName(String name)
    {
        BookDetails bd=null;
      try {
          Session s=getOpenSession();
          Query query=s.createQuery("from BookDetails as bd where bd.name like:name");
          query.setString("name", name);
          bd=(BookDetails)query.uniqueResult();
          s.close();
         } catch (Exception e) {
          }
          if(bd!=null)
              return bd;
          else
              return null;

       
       
        
    }
    public Session getOpenSession()
    {
        return getSessionFactory().openSession();
    }
    public void buyBooks(ShoppingCart cart) throws 
Exception
    {
    
      
       Collection items = cart.getItems();
       Iterator i = items.iterator();
       try{
                    while(i.hasNext())
               {
                   ShoppingCartItem sci=(ShoppingCartItem) i.next();
                   BookDetails bd=(BookDetails) sci.getItem();
                   String id=bd.getBookId();
                   int quantity=sci.getQuantity();
                   buyBook(id,quantity);
               }
                  
           
       }catch (Exception ex) {
        
         throw ex;
     
    }
      
      
    }
     public void buyBook(String bookId, int quantity) 
throws Exception
       {
         Session s=getOpenSession();
         int oldSaleAmount=0;
         Transaction tx=s.beginTransaction();
         try
         {
             /*BookDetails book=(BookDetails) s.get(BookDetails.class, bookId);
             oldSaleAmount=book.getSaleAmount();
             book.setSaleAmount(oldSaleAmount+quantity);
             
             javax.swing.JOptionPane.showMessageDialog(null, book.getName());
             s.update(book);
             javax.swing.JOptionPane.showMessageDialog(null, book.getName());*/
             
             BookDetails book=(BookDetails) s.get(BookDetails.class, bookId);
             oldSaleAmount=book.getSaleAmount();
             Query query=s.createQuery("update BookDetails as bd set bd.saleAmount=? where bd.bookId=?");
             query.setInteger(0, quantity+oldSaleAmount);
             query.setString(1, bookId);
             query.executeUpdate();
              
               
           
               
        
            tx.commit();
             
         }catch(Exception ex){
         tx.rollback();
         throw ex;
         }finally{
           s.close();
         }
                 
           
       }
     public Collection getBookTypeSet()
     {
         Session s=getSessionFactory().openSession();
         Query q=s.createQuery("from Booktype");
         List list=q.list();
         return list;
         
     }
     public Booktype getBooktype(String id)
     {
       
     Session session1=getSessionFactory().openSession();
     //Query query=session1.createQuery("from Booktype as bt where bt.id=?");
     //query.setParameter(0, id);
     //Booktype bt=(Booktype) query.uniqueResult();
     Booktype bt=(Booktype) session1.load(Booktype.class, id);
      if(bt!=null)
          return bt;
      else         
          return null;
     }
     public Collection getBooksSort()
     {
         Session s=getSessionFactory().openSession();
         Query q=s.createQuery("from BookDetails as bd order by bd.saleAmount desc");
         List list=q.list();
         return list;
         
         
         
     }
}