package edu.rice.rubis.beans; import java.rmi.*; import javax.ejb.*; import javax.naming.Context; import javax.naming.InitialContext; import javax.rmi.PortableRemoteObject; import java.util.GregorianCalendar; /** * ItemBean is an entity bean with "container managed persistence". * The state of an instance is stored into a relational database. * The following table should exist:

* 

 * CREATE TABLE items (
 *    id            INTEGER UNSIGNED NOT NULL UNIQUE,
 *    name          VARCHAR(100),
 *    description   TEXT,
 *    initial_price FLOAT UNSIGNED NOT NULL,
 *    quantity      INTEGER UNSIGNED NOT NULL,
 *    reserve_price FLOAT UNSIGNED DEFAULT 0,
 *    buy_now       FLOAT UNSIGNED DEFAULT 0,
 *    nb_of_bids    INTEGER UNSIGNED DEFAULT 0,
 *    max_bid       FLOAT UNSIGNED DEFAULT 0,
 *    start_date    DATETIME,
 *    end_date      DATETIME,
 *    seller        INTEGER,
 *    category      INTEGER,
 *    PRIMARY KEY(id),
 *    INDEX seller_id (seller),
 *    INDEX category_id (category)
 * );
 *
* @author Emmanuel Cecchet and Julie Marguerite * @version 1.1 */ public abstract class OldItemBean implements EntityBean { private EntityContext entityContext; private transient boolean isDirty; // used for the isModified function /** * Set item id. * * @since 1.0 */ public abstract void setId(Integer id); /** * Get item id. * * @return item id * @since 1.0 */ public abstract Integer getId(); /** * Get item name. This description is usually a short description of the item. * * @return item name * @since 1.0 */ public abstract String getName(); /** * Get item description . This is usually an HTML file describing the item. * * @return item description * @since 1.0 */ public abstract String getDescription(); /** * Get item initial price set by the seller. * * @return item initial price * @since 1.0 */ public abstract float getInitialPrice(); /** * Get how many of this item are to be sold. * * @return item quantity * @since 1.0 */ public abstract int getQuantity(); /** * Get item reserve price set by the seller. The seller can refuse to sell if reserve price is not reached. * * @return item reserve price * @since 1.0 */ public abstract float getReservePrice(); /** * Get item Buy Now price set by the seller. A user can directly by the item at this price (no auction). * * @return item Buy Now price * @since 1.0 */ public abstract float getBuyNow(); /** * Get item maximum bid (if any) for this item. This value should be the same as doing 
SELECT MAX(bid) FROM bids WHERE item_id=?
* * @return current maximum bid or 0 if no bid * @since 1.1 */ public abstract float getMaxBid(); /** * Get number of bids for this item. This value should be the same as doing 
SELECT COUNT(*) FROM bids WHERE item_id=?
* * @return number of bids * @since 1.1 */ public abstract int getNbOfBids(); /** * Start date of the auction in the format 'YYYY-MM-DD hh:mm:ss' * * @return start date of the auction * @since 1.0 */ public abstract String getStartDate(); /** * End date of the auction in the format 'YYYY-MM-DD hh:mm:ss' * * @return end date of the auction * @since 1.0 */ public abstract String getEndDate(); /** * Give the user id of the seller * * @return seller's user id * @since 1.0 */ public abstract Integer getSellerId(); /** * Give the category id of the item * * @return item's category id * @since 1.0 */ public abstract Integer getCategoryId(); /** * Set a new item name * * @param newName item name * @since 1.0 */ public abstract void setName(String newName); /** * Set a new item description * * @param newDescription item description * @since 1.0 */ public abstract void setDescription(String newDescription); /** * Set a new initial price for the item * * @param newInitialPrice item initial price * @since 1.0 */ public abstract void setInitialPrice(float newInitialPrice); /** * Set a new item quantity * * @param qty item quantity * @since 1.0 */ public abstract void setQuantity(int qty); /** * Set a new reserve price for the item * * @param newReservePrice item reserve price * @since 1.0 */ public abstract void setReservePrice(float newReservePrice); /** * Set a new Buy Now price for the item * * @param newBuyNow item Buy Now price * @since 1.0 */ public abstract void setBuyNow(float newBuyNow); /** * Set item maximum bid. This function checks if newMaxBid is greater * than current maxBid and only updates the value in this case. * * @param newMaxBid new maximum bid * @since 1.1 */ public abstract void setMaxBid(float newMaxBid); /** * Set the number of bids for this item * * @param newNbOfBids new number of bids * @since 1.1 */ public abstract void setNbOfBids(int newNbOfBids); /** * Set a new beginning date for the auction * * @param newDate auction new beginning date * @since 1.0 */ public abstract void setStartDate(String newDate); /** * Set a new ending date for the auction * * @param newDate auction new ending date * @since 1.0 */ public abstract void setEndDate(String newDate); /** * Set a new seller identifier. This id must match * the primary key of the users table. * * @param id seller id * @since 1.0 */ public abstract void setSellerId(Integer id); /** * Set a new category identifier. This id must match * the primary key of the category table. * * @param id category id * @since 1.0 */ public abstract void setCategoryId(Integer id); /** * Get the seller's nickname by finding the Bean corresponding * to the user. * * @return nickname * @since 1.0 */ public String getSellerNickname() { Context initialContext = null; try { initialContext = new InitialContext(); } catch (Exception e) { System.err.print("Cannot get initial context for JNDI: " + e); return null; } // Try to find the user nick name corresponding to the sellerId UserLocalHome uHome; try { uHome = (UserLocalHome)initialContext.lookup("java:comp/env/ejb/User"); } catch (Exception e) { System.err.print("Cannot lookup User: " +e); return null; } try { UserLocal u = uHome.findByPrimaryKey(new UserPK(getSellerId())); return u.getNickName(); } catch (Exception e) { System.err.print("This user does not exist (got exception: " +e+")
"); return null; } } /** * Get the category name by finding the Bean corresponding to the category Id. * * @return category name * @since 1.0 */ public String getCategoryName() { Context initialContext = null; try { initialContext = new InitialContext(); } catch (Exception e) { System.err.print("Cannot get initial context for JNDI: " + e); return null; } // Try to find the CategoryName corresponding to the categoryId CategoryLocalHome cHome; try { cHome = (CategoryLocalHome)initialContext.lookup("java:comp/env/ejb/Category"); } catch (Exception e) { System.err.print("Cannot lookup Category: " +e); return null; } try { CategoryLocal c = cHome.findByPrimaryKey(new CategoryPK(getCategoryId())); return c.getName(); } catch (Exception e) { System.err.print("This category does not exist (got exception: " +e+")
"); return null; } } /** * Add one bid for this item * * @since 1.1 */ public void addOneBid() { setNbOfBids(getNbOfBids()+1); isDirty = true; // the bean content has been modified } /** * This method is used to create a new Item Bean. Note that the item id * is automatically generated by the database (AUTO_INCREMENT) on the * primary key. * * @param itemName short item designation * @param itemDescription long item description, usually an HTML file * @param itemInitialPrice initial price fixed by the seller * @param itemQuantity number to sell (of this item) * @param itemReservePrice reserve price (minimum price the seller really wants to sell) * @param itemBuyNow price if a user wants to buy the item immediatly * @param duration duration of the auction in days (start date is when the method is called and end date is computed according to the duration) * @param itemSellerId seller id, must match the primary key of table users * @param itemCategoryId category id, must match the primary key of table categories * * * @exception CreateException if an error occurs * @since 1.0 */ public OldItemPK ejbCreate(Integer itemId, String itemName, String itemDescription, float itemInitialPrice, int itemQuantity, float itemReservePrice, float itemBuyNow, int duration, Integer itemSellerId, Integer itemCategoryId) throws CreateException { GregorianCalendar start = new GregorianCalendar(); setId(itemId); setName(itemName); setDescription(itemDescription); setInitialPrice(itemInitialPrice); setQuantity(itemQuantity); setReservePrice(itemReservePrice); setBuyNow(itemBuyNow); setSellerId(itemSellerId); setCategoryId(itemCategoryId); setNbOfBids(0); setMaxBid(0); setStartDate(TimeManagement.dateToString(start)); setEndDate(TimeManagement.dateToString(TimeManagement.addDays(start, duration))); return null; } /** This method just set an internal flag to reload the id generated by the DB */ public void ejbPostCreate(Integer itemId, String itemName, String itemDescription, float itemInitialPrice, int itemQuantity, float itemReservePrice, float itemBuyNow, int duration, Integer itemSellerId, Integer itemCategoryId) { isDirty = true; // the id has to be reloaded from the DB } /** Persistence is managed by the container and the bean becomes up to date */ public void ejbLoad() { isDirty = false; } /** Persistence is managed by the container and the bean becomes up to date */ public void ejbStore() { isDirty = false; } /** This method is empty because persistence is managed by the container */ public void ejbActivate(){} /** This method is empty because persistence is managed by the container */ public void ejbPassivate(){} /** This method is empty because persistence is managed by the container */ public void ejbRemove() throws RemoveException {} /** * Sets the associated entity context. The container invokes this method * on an instance after the instance has been created. * * This method is called in an unspecified transaction context. * * @param context An EntityContext interface for the instance. The instance should * store the reference to the context in an instance variable. * @exception EJBException Thrown by the method to indicate a failure * caused by a system-level error. */ public void setEntityContext(EntityContext context) { entityContext = context; } /** * Unsets the associated entity context. The container calls this method * before removing the instance. This is the last method that the container * invokes on the instance. The Java garbage collector will eventually invoke * the finalize() method on the instance. * * This method is called in an unspecified transaction context. * * @exception EJBException Thrown by the method to indicate a failure * caused by a system-level error. */ public void unsetEntityContext() { entityContext = null; } /** * Returns true if the beans has been modified. * It prevents the EJB server from reloading a bean * that has not been modified. * * @return a boolean value */ public boolean isModified() { return isDirty; } /** * Display item information as an HTML table row * * @return a String containing HTML code * @since 1.0 */ public String printItem() { return ""+getName()+ ""+getMaxBid()+ ""+getNbOfBids()+ ""+getEndDate()+ "\n"; } }