public CoursePictureModel GetPicture(int companyID, int courseID)
{
CoursePictureModel result;
if (IsPictureInCache(companyID, courseID))
{
result = GetPictureFromCache(companyID, courseID);
}
else
{
result = imageStorage.GetCoursePicture(companyID, courseID);
if (result == null)
{
throw new CourseNotFoundException();
}
object locker = GetOrAddConcurrentKey(companyID, courseID);
lock (locker)
{
if (!IsPictureInCache(companyID, courseID))
{
SavePictureToCache(result);
}
}
}
return(result);
}