@Override
    public int getCachedSize() throws CannotCalculateSizeException
    {
        int size = super.getCachedSize(); // parent.
        size += CacheSizes.sizeOfMap( nodes );
        size += CacheSizes.sizeOfInt(); // associationPolicy
        size += CacheSizes.sizeOfCollection( associationTrusted );
        size += CacheSizes.sizeOfInt(); // maxLeafNodes
        return size;
    }
Only those on a whitelist may associate leaf nodes with the collection.
xmppserver/src/main/java/org/jivesoftware/openfire/pubsub/CollectionNode.java