/// <summary>
/// Lookup an item from the metadata cache for a given service type.
/// </summary>
/// <param name="serviceType">Service type for which we want to lookup metadata.</param>
/// <returns>MetadataCacheItem for the service type. Null if there is no item in the cache for the given service type.</returns>
internal static MetadataCacheItem TryLookup(Type serviceType)
{
MetadataCacheItem item;
var key = new MetadataCacheKey(serviceType);
_cache.TryGetValue(key, out item);
return(item);
}
/// <summary>
/// Add an MetadataCacheItem object to the cache for a given service.
/// </summary>
/// <param name="serviceType">Type of the service class</param>
/// <param name="item">Item to be added to the cache</param>
/// <returns>Item that was added to the cache</returns>
internal static MetadataCacheItem AddCacheItem(Type serviceType, MetadataCacheItem item)
{
MetadataCacheItem item2;
var key = new MetadataCacheKey(serviceType);
// Use a double check lock for concurrency.
if (!_cache.TryGetValue(key, out item2))
{
lock (_lockObject)
{
if (!_cache.TryGetValue(key, out item2))
{
_cache.Add(key, item);
item2 = item;
}
}
}
return(item2);
}