How to use SOA in SmartClient

I would like to develop a multi-tire architecture with web server and application. Users will browse the web server (smartclient). The smartclient will not connect to the database. But it will make a web service (e.g. REST) to call the application server which connect to the data base for data retrieval. My question is how to use the
Smartclient without database connected as I cannot use “DataSource” nor Hibernate.

Do you have any CRUD example which it invokes java class after user add/change/ delete.