checkerbean.java

卡内基梅隆大学软件工程课件,很全面

/*
 *
 * Copyright 2001 Sun Microsystems, Inc. All Rights Reserved.
 * 
 * This software is the proprietary information of Sun Microsystems, Inc.  
 * Use is subject to license terms.
 * 
 */

import java.util.*;
import javax.ejb.*;
import javax.naming.*;

public class CheckerBean implements SessionBean {

   String customerName;

   public void ejbCreate(String person) {

      customerName = person;
   }

   public double applyDiscount(double amount) {

      try {

         double discount;
   
         Context initial = new InitialContext();
         Context environment = (Context)initial.lookup("java:comp/env");
   
         Double discountLevel = (Double)environment.lookup("Discount Level");
         Double discountPercent = (Double)environment.lookup("Discount Percent");
   
         if (amount >= discountLevel.doubleValue()) {
            discount = discountPercent.doubleValue();
         }
         else {
            discount = 0.00;
         }
    
         return amount * (1.00 - discount);

      } catch (NamingException ex) {
           throw new EJBException("NamingException: " + ex.getMessage());
      }
   }

   public CheckerBean() {}
   public void ejbRemove()  {}
   public void ejbActivate() {}
   public void ejbPassivate() {}
   public void setSessionContext(SessionContext sc) {}
}