@Override
    public int getCachedSize() throws CannotCalculateSizeException
    {
        int size = super.getCachedSize(); // parent.
        size += CacheSizes.sizeOfBoolean(); // persistPublishedItems
        size += CacheSizes.sizeOfInt(); // maxPublishedItems
        size += CacheSizes.sizeOfInt(); // maxPayloadSize
        size += CacheSizes.sizeOfBoolean(); // sendItemSubscribe
        // The 'lastPublished' field is transient - it is reloaded from the provider on-demand.
        return size;
    }
Purges items that were published to the node. Only owners can request this operation.
This operation is only available for nodes configured to store items in the database. All
published items will be deleted except the last published item.
xmppserver/src/main/java/org/jivesoftware/openfire/pubsub/LeafNode.java