public static UniqueIdentifier getUniqueIdentifier(LeafNode node, String itemId)
    {
        return getUniqueIdentifier( node.getUniqueIdentifier().getServiceIdentifier().getServiceId(), node.getUniqueIdentifier().getNodeId(), itemId );
    }
Returns a value that uniquely identifies this published item in the XMPP domain.

@param node Node for the published item
@param itemId Id for the published item (unique within the node)
@return Unique identifier for this item
xmppserver/src/main/java/org/jivesoftware/openfire/pubsub/PublishedItem.java