cart.java

来自「webwork source」· Java 代码 · 共 92 行

package webwork.examples.i18n;

import java.util.ArrayList;
import java.util.List;

/**
 * This code is an adaptation of the I18N example from the JavaWorld article by Govind Seshadri.
 * http://www.javaworld.com/javaworld/jw-03-2000/jw-03-ssj-jsp_p.html
 */
public class Cart 
{
   List items;

   public void addItem(CD cd, int quantity)
   {
      if (items == null)
         items = new ArrayList();
   
      for (int i = 0; i < items.size(); i++)
      {
         CartItem ci = (CartItem)items.get(i);
         if (cd.equals(ci.cd))
         {
            ci.addQuantity(quantity);
            return;
         }
      }
      
      items.add(new CartItem(cd, quantity));
   }
   
   public void removeItem(CD cd)
   {
      for (int i = 0; i < items.size(); i++)
      {
         CartItem ci = (CartItem)items.get(i);
         if (cd.equals(ci.cd))
         {
            items.remove(ci);
            
            if (items.size() == 0)
               items = null;
            
            return;
         }
      }
   }
   
   public List getItems()
   {
      return items;
   }

   public double getTotal()
   {
      double total = 0;
      for (int i = 0; i < items.size(); i++)
      {
         CartItem ci = (CartItem)items.get(i);
         total += ci.getCd().getPrice() * ci.getQuantity();
      }
      return total;
   }
   
   static public class CartItem
   {
      int qty;
      CD cd;
      
      CartItem(CD cd, int qty)
      {
         this.cd = cd;
         addQuantity(qty);
      }
      
      public void addQuantity(int qty)
      {
         this.qty += qty;
      }
      
      public int getQuantity()
      {
         return qty;
      }
      
      public CD getCd()
      {
         return cd;
      }
   }
}