package cbcc.org.listeners;

//imports
import cbcc.org.DAO.OrderDAO;
import java.util.LinkedList;
import java.util.List;
import javax.servlet.ServletContext;
import javax.servlet.ServletContextListener;
import javax.servlet.ServletContextEvent;

/**
 * Class OrderListener  - Web application lifecycle listener for orders.
 *
 * @author 
 * @version 1.1
 */

public class OrderListener implements ServletContextListener {
    /**
     * ### Method from ServletContextListener ###
     *
     * Called when a Web application is first ready to process requests
     * (i.e. on Web server startup and when a context is added or reloaded).
     *
     * For example, here might be database connections established
     * and added to the servlet context attributes.
     */
    public void contextInitialized(ServletContextEvent evt) {
        //get context
        ServletContext context = evt.getServletContext();
        //set filename
        OrderDAO.setFilename(context.getRealPath("/data/Order.xml"));
        
        //create dao
        OrderDAO orderDAO = new OrderDAO();
         
        //get list from dao
        List ordersList = (List) orderDAO.retrieveOrders();
        
        //store in context
        evt.getServletContext().setAttribute("ordersList", ordersList);
    }
    
    /**
     * ### Method from ServletContextListener ###
     *
     * Called when a Web application is about to be shut down
     * (i.e. on Web server shutdown or when a context is removed or reloaded).
     * Request handling will be stopped before this method is called.
     *
     * For example, the database connections can be closed here.
     */
    public void contextDestroyed(ServletContextEvent evt) {
        
        //create dao
        OrderDAO orderDAO = new OrderDAO();
        
        orderDAO.setOrdersList((LinkedList) evt.getServletContext().getAttribute("ordersList"));
        
        //update
        orderDAO.update((LinkedList) evt.getServletContext().getAttribute("ordersList"));
    }
}