ZK Tree Load on Demand, Render on Demand following Bai Ben's approach http://ben-bai.blogspot.com/2013/01/zk-tree-rod-and-load-on-demand.html
RODTreeModel, RODTreeNode, and RODTreeNodeData are core classes that you can reuse across ZK projects (see link above.)
The main differences in this project vs Bai's are:
It's illustrated using a typical type of domain value object you might be working with (in this case a simple "Person" object.) Bai's project is great but it could confuse some a bit since it's illustrating the usage with traversing a File system, versus a typical type of crud call to just fetch your children from the DB.
Uses a service class that you pass to the PersonRODTreeNodeData object. [ When setting up your own project feel free to instantiate the service class directly in PersonRODTreeNodeData and don't bother passing it via the constructor, but since 'in real life' I use Spring (not illustrated in this project), I find it easier in this case to pass the service class directly vs having to look up the bean from Spring's app context and use Prototype scope.
mvn clean install
move the target/zk-tree-ondemand.war file to your app server of choice and then http://localhost:8080/zk-tree-ondemand/