contextlistener.java

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/*
 *
 * Copyright 2002 Sun Microsystems, Inc. All Rights Reserved.
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 * without modification, are permitted provided that the following
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 * contributors may be used to endorse or promote products derived
 * from this software without specific prior written permission.
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 * This software is provided "AS IS," without a warranty of any
 * kind. ALL EXPRESS OR IMPLIED CONDITIONS, REPRESENTATIONS AND
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package listeners;

import database.BookDBAO;
import javax.servlet.*;

public final class ContextListener
    implements ServletContextListener {
    private ServletContext context = null;

    public void contextInitialized(ServletContextEvent event) {
         context = event.getServletContext();
         
         try {
            BookDBAO bookDBAO = new BookDBAO();
            context.setAttribute("bookDBAO", bookDBAO);
         } catch (Exception ex) {
            System.out.println("Couldn't create bookstore database bean: " + ex.getMessage());
         }
    }
      
    public void contextDestroyed(ServletContextEvent event) {
         context = event.getServletContext();
         BookDBAO bookDBAO = (BookDBAO)context.getAttribute("bookDBAO");
         if (bookDBAO != null)
            bookDBAO.remove();
         context.removeAttribute("bookDBAO");
    }
}