public void UnsafeRemove(CollectibleNode node)
{
if (directory.ContainsKey(node.GetKey()))
{
directory.Remove(node.GetKey());
}
}
// This method must be called inside a writable lock
public void UnsafeAdd(CollectibleNode node)
{
Fx.Assert(rwLock.IsWriteLockHeld, "This method can be called only when the WriterLock is acquired");
writeCounter++;
directory.Add(node.GetKey(), node);
node.LastCounter = Interlocked.Increment(ref counter);
}
public void Touch(TKey key)
{
rwLock.EnterReadLock();
try
{
CollectibleNode node = UnsafeGet(key);
if (node != null)
{
// Record the last counter in the node. We don't take a writer lock here because the counter does
// not have to be very accurate.
node.LastCounter = Interlocked.Increment(ref counter);
}
}
finally
{
rwLock.ExitReadLock();
}
}
public static int CounterLessThan(CollectibleNode x, CollectibleNode y)
{
return(x.LastCounter - y.LastCounter);
}