You can work directly with a database from your JSPs but it is not recommended. Moving the database code out of your servlet and into a bean or some other Java class makes it much easier to test and re-use.
That being said, perform a Google search for "JDBC TUTORIAL" and you will find plenty of code samples.
Originally posted by K Vidhyakar: thanks a lot.. wil i be able to call a normal class from any jsp file?
If by normal class, you mean a packaged java class that is made available to the web application (in either WEB-INF/classes, WEB-INF/lib, or one of the shared directories), yes.
You can do regular JDBC in a JSP page, but it will get messy, and maintaining that code will be difficult. If it's all proof of concept stuff as you're learning, I guess it's okay.
Here's a little tutorial on MVC and how JSPs should fit into a proper application design. You might find it interesting:
