public virtual bool ContainsKey(Job key)
 {
     try
     {
         @lock.readLock().@lock();
         // if we are using a threaded cache we return true if the tile is still in the
         // queue to reduce double rendering
         return(this.lruCache.ContainsKey(key.Key));
     }
     finally
     {
         @lock.readLock().unlock();
     }
 }