In Tree View, On Click on the Parent node, the child records needs to be loaded

We are developing a thin client browser based application using struts frame work, where the User Interface contains Tree View.
When I click on the Parent node, the controller should hit the database and get the child record.
I am able to create the Tree view using Java script. I would like to know, Is there any possibility to get the data dynamically by invoking a Java bean from a Java script function with out
using the Live connect feature. If Yes then, how can I pass the Java script variable to Java function as parameter?

Please suggest the best approach to implement the above specified requirement.

Regards,
Nirmala