public Option <TWeakOwningKey> GetPossibleWeakKeyFromValue(TContained contained)
{
lock (mLock)
{
foreach (var wrn in ContainedToKeyAndNeutralizeKillShot.GetValueIfPresent(contained).ToEnumerable())
{
if (wrn.Item1.TryGetTarget(out var possible))
{
return(Some(possible));
}
}
return(None <TWeakOwningKey>());
}
}
private Either <TWeakOwningKey, T> AddUtility <T>(TContained contained, Func <TWeakOwningKey> buildNewResourceKey, Func <TContained, TWeakOwningKey, T> toReturnIfAlreadyExists)
{
lock (mLock)
{
foreach (var wrn in ContainedToKeyAndNeutralizeKillShot.GetValueIfPresent(contained).ToEnumerable())
{
if (wrn.Item1.TryGetTarget(out var possible))
{
return(Either <TWeakOwningKey, T> .FromRight(toReturnIfAlreadyExists(contained, possible)));
}
else
{
// ** IMPORTANT ** - we failed to get the weak back - the weak-key is gone, ergo while there is a contained object here, it's to be considered defunct.
// However, theoretically, an outstanding killshot could be hanging on this lock to remove ContainedToKey.
wrn.Item2(); // don't want it to come back and kill the one we will add
ContainedToKeyAndNeutralizeKillShot.Remove(contained); // remove it ourself, now that noone else will
// Will fall through and rebuild the entry.
}
}
// build it.
var resourceKey = buildNewResourceKey();
var(newKeyHolder, neutralizeKillShot) = NewKeyHolderAndNeutralizeKillShot(mLock, ContainedToKeyAndNeutralizeKillShot, contained);
KeyToContained.Add(
resourceKey,
Tuple.Create(
contained,
newKeyHolder));
ContainedToKeyAndNeutralizeKillShot.Add(contained, Tuple.Create(new WeakReference <TWeakOwningKey>(resourceKey), neutralizeKillShot));
return(Either <TWeakOwningKey, T> .FromLeft(resourceKey));
}
}
