Java Database Connectivity (JDBC)

I've been studying JDBC for months now and have worked on some test projects...but in all e-books and tutorials I've read so far they only teach me ODBC connection, where I had to set up my System DSN to make the connection work.

Can you guys show a sample code of how to connect by just using a connection string(like in ASP/ADO)? I'm using either MSAccess or SQLServer for back-end so an example for each would be greatly appreciated....thank you. :)