catalogfacade.java

仿照著名的petstore写的网上书店

        return items;
    }
    
    /**
     * Gets a list of all the zipcode/city/state for autocomplete on user forms
     * Need to enhance so that returned list is cached for reuse at application scope
     * and held as member field of facade.
     * @returns a List of ZipLocation objects
     */
    @SuppressWarnings("unchecked") 
    public List<ZipLocation> getZipCodeLocations(String city, int start, int chunkSize){
        EntityManager em = emf.createEntityManager();
        String pattern = "'"+city.toUpperCase()+"%'";
        Query query = em.createQuery("SELECT  z FROM ZipLocation z where UPPER(z.city) LIKE "+pattern);
        List<ZipLocation>  zipCodeLocations = query.setFirstResult(start).setMaxResults(chunkSize).getResultList();
        em.close();
        return zipCodeLocations;
    }
    
    @SuppressWarnings("unchecked") 
    public List<Product> getProducts(String catID){
        EntityManager em = emf.createEntityManager();
        List<Product> products = em.createQuery("SELECT p FROM Product p WHERE p.categoryID LIKE :categoryID")
        .setParameter("categoryID", catID).getResultList();
        em.close();
        return products;
    }
    
    @SuppressWarnings("unchecked") 
    public List<Item> getItems(String prodID){
        EntityManager em = emf.createEntityManager();
        List<Item> items = em.createQuery("SELECT i FROM Item i WHERE i.productID LIKE :productID AND i.disabled = 0")
        .setParameter("productID", prodID).getResultList();
        em.close();
        return items;
    }
    
    public Category getCategory(String categoryID){
        EntityManager em = emf.createEntityManager();
        Category result = em.find(Category.class,categoryID);
        em.close();
        return result;
    }
    
    public Item getItem(String itemID){
        EntityManager em = emf.createEntityManager();
        Item result = em.find(Item.class,itemID);
        em.close();
        return result;
    }
    
    /**
     * Method to add an item with tags that are added using the addTag method
     *
     */
    public String addItem(Item item){
        EntityManager em = emf.createEntityManager();
        try{
            utx.begin();
            em.joinTransaction();
            for(Tag tag : item.getTags()) {
                tag.incrementRefCount();
                tag.getItems().add(item);
                em.merge(tag);
            }
            em.persist(item);
            utx.commit();
            // index item
            if(bDebug) System.out.println("\n***Item id of new item is : " + item.getItemID());
            indexItem(new IndexDocument(item));
            
        } catch(Exception exe){
            try {
                utx.rollback();
            } catch (Exception e) {}
            throw new RuntimeException("Error persisting item", exe);
        } finally {
            em.close();
        }
        return item.getItemID();
    }
    
    public void updateItem(Item item){
        EntityManager em = emf.createEntityManager();
        try{
            utx.begin();
            em.merge(item);
            utx.commit();

            // update index using delete/insert method (only one available)
            UpdateIndex.deleteIndex(PetstoreConstants.PETSTORE_INDEX_DIRECTORY, item.getItemID());
            indexItem(new IndexDocument(item));
        } catch(Exception exe){
            try {
                utx.rollback();
            } catch (Exception e) {}
            throw new RuntimeException("Error updating rating", exe);
        } finally {
            em.close();
        }
        

        
    }
    
    public Collection doSearch(String querryString){
        EntityManager em = emf.createEntityManager();
        Query searchQuery = em.createNativeQuery("SELECT * FROM Item WHERE (name LIKE ? OR description LIKE ?) AND disabled = 0" );
        searchQuery.setParameter(1, "%"+querryString+"%");
        searchQuery.setParameter(2,"%"+querryString+"%");
        
        Collection results = searchQuery.getResultList();
        em.close();
        return results;
    }
    
    
    public void addTagsToItemId(String sxTags, String itemId) {
        EntityManager em = emf.createEntityManager();
        // now parse tags for item
        Item item=getItem(itemId);
        StringTokenizer stTags=new StringTokenizer(sxTags, " ");
        String tagx=null;
        Tag tag=null;
        while(stTags.hasMoreTokens()) {
            tagx=stTags.nextToken().toLowerCase();
            if(!item.containsTag(tagx)) {
                // tag doesn't exist so add tag
                if(bDebug) System.out.println("Adding TAG = " + tagx);
                tag=addTag(tagx);
                //tag.incrementRefCount();
                tag.getItems().add(item);
                tag.incrementRefCount();
                item.getTags().add(tag);
            }
        }
        try {
            // persist data
            utx.begin();
            em.joinTransaction();
            em.merge(item);
            for( Tag tagz : item.getTags()) {
                if(bDebug) System.out.println("\n***Merging tag = " + tagz.getTag());
                em.merge(tagz);
            }
            utx.commit();
            
            // update indexes
            UpdateIndex update=new UpdateIndex();
            update.updateDocTag(PetstoreConstants.PETSTORE_INDEX_DIRECTORY, "tag" , item.tagsAsString(), item.getItemID(), UpdateIndex.REPLACE_FIELD);
            
        } catch(Exception exe){
            try {
                utx.rollback();
            } catch (Exception e) {}
            throw new RuntimeException("Error persisting tag", exe);
        } finally {
            em.close();
        }
    }
    
    
    @SuppressWarnings("unchecked") 
    public Tag addTag(String sxTag){
        EntityManager em = emf.createEntityManager();
        Tag tag=null;
        try {
            List<Tag> tags=em.createQuery("SELECT t FROM Tag t WHERE t.tag = :tag").setParameter("tag", sxTag).getResultList();
            if(tags.isEmpty()) {
                // need to create tag and set flag to add reference item
                tag=new Tag(sxTag);
                // persist data
                utx.begin();
                em.joinTransaction();
                em.persist(tag);
                utx.commit();
            } else {
                // see if item already exists in tag
                tag=tags.get(0);
            }
            
        } catch(Exception exe){
            try {
                utx.rollback();
            } catch (Exception e) {}
            throw new RuntimeException("Error persisting tag", exe);
        } finally {
            em.close();
        }
        return tag;
    }
    
    
    @SuppressWarnings("unchecked") 
    public List<Tag> getTagsInChunk(int start, int chunkSize) {
        EntityManager em = emf.createEntityManager();
        Query query = em.createQuery("SELECT t FROM Tag t ORDER BY t.refCount DESC, t.tag");
        List<Tag> tags = query.setFirstResult(start).setMaxResults(chunkSize).getResultList();
        em.close();
        return tags;
    }

    
    @SuppressWarnings("unchecked") 
    public Tag getTag(String sxTag) {
        Tag tag=null;
        EntityManager em = emf.createEntityManager();
        List<Tag> tags=em.createQuery("SELECT t FROM Tag t WHERE t.tag = :tag").setParameter("tag", sxTag).getResultList();
        em.close();
        if(tags != null && !tags.isEmpty()) {
            tag=tags.get(0);
        }
        return tag;
    }


    private void indexItem(IndexDocument indexDoc) {
        // Add document to index
        if(bDebug) System.out.println("\n*** document to index - " + indexDoc);
        Indexer indexer=null;
        try {
            indexer=new Indexer(PetstoreConstants.PETSTORE_INDEX_DIRECTORY, false);
            PetstoreUtil.getLogger().log(Level.FINE, "Adding document to index: " + indexDoc.toString());
            indexer.addDocument(indexDoc);
        } catch (Exception e) {
            PetstoreUtil.getLogger().log(Level.WARNING, "index.exception", e);
            e.printStackTrace();
        } finally {
            try {
                // must close file or will not be able to reindex
                if(indexer != null) {
                    indexer.close();
                }
            } catch (Exception ee) {
                ee.printStackTrace();
            }
        }
    }
    
}