public WeakDictionary()
{
if (typeof(K) == typeof(WeakReference))
{
throw new InvalidOperationException();
}
this.cleanupSyncObject = new object();
storage = new Dictionary <WeakDictionary <K, V> .WeakKey, V>();
// kick off the cleanup process...
WeakDictionaryCleanupToken.CreateCleanupToken(this);
}
public void Cleanup()
{
List <WeakKey> toClean = null;
// First determine what items have died and can be removed...
lock (cleanupSyncObject)
{
foreach (var key in storage.Keys)
{
bool isAlive, needsCleanup;
key.GetValue(out isAlive, out needsCleanup);
if (!isAlive)
{
if (toClean == null)
{
toClean = new List <WeakKey>();
}
toClean.Add(key);
}
}
}
if (toClean != null)
{
// Second go and remove them...
lock (cleanupSyncObject)
{
// If toClean is > some % of the total size it is probably better
// just to create a new dictionary and migrate some set of items over
// wholesale? It is unclear whether or not this is true.
foreach (var key in toClean)
{
storage.Remove(key);
}
}
}
WeakDictionaryCleanupToken.CreateCleanupToken(this);
}
public static void CreateCleanupToken(WeakDictionary <K, V> storage)
{
// Create one of these, the work is done when it is finalized which
// will be at some indeterminate point in the future...
WeakDictionaryCleanupToken token = new WeakDictionaryCleanupToken(storage);
}
