Security: How to create custom realm class which is connected with DB.

I want to know how to create custom realm in Sun Java System Application Server version 9.

I need to config and implement with security more than which supported by application server.

Please help me and give some code sinnpet for the following.

1. How to create custom realm
2. How to create class for custom realm
3. How to connect with database.
4. How to map with application.

Thanks
Kyaw Htoo.

Please do not post the same question to multiple forums, as it is confusing and potentially time-wasting if multiple identical conversations take place simultaneously. I have deleted the other copy, because this one is more specific.

Thanks Ulf Dittmer for your advice.

Kyaw Htoo.

A quick Google search finds this highly relevant page.