public void AddItems(Item[] items, string producerEmail)
 {
     component.AddItems(items, producerEmail);
     lock (itemDictionaryLock)
     {
         FillCacheIfNeeded(producerEmail);
         foreach (Item item in items)
         {
             cachedItems[producerEmail].Add(item.ProductNumber, item);
         }
     }
 }
 public void AddItems(Item[] items, string producerEmail)
 {
     CheckAllDifferent(items);
     CheckAllNotPresent(items, producerEmail);
     component.AddItems(items, producerEmail);
 }