public boolean containsNode(final ExplorerNode node) {
        return keyToNodeMap.containsKey(getNodeKey(node));
    }
//     * Replaces an existing node with the supplied one, based on the unique key
//     * of the new node. The new node will be linked to the previous node's parent
//     * and children. If the key is not found an exception will be thrown.
//     * Intended for changing other properties of a node, e.g. the alerts on it.
//     *
//     * MUST be done while under an exclusive lock on this model.
//
stroom-explorer/stroom-explorer-impl/src/main/java/stroom/explorer/impl/AbstractTreeModel.java