Java EE (Java Enterprise Edition) General Discussion

I wanted to conceptually know ...

If I have a class specifically doing some quering to database and giving results to jsp and servlet ... does this make sense? Static methods are ok ? Is it secure enough if I have all connection classes local to a method? can i make the connection global instead without compromising security ?

For example:

public class DatabaseUtility{

public static Sring getUsername(String employeeid)
{
  Connection conn = ...........
  Statement stmt = ........
 rs executes query and gets a username and returns it...
}

public static Sring getAddress(String employeeid)
{
  Connection conn = ...........
  Statement stmt = ........
 rs executes query and gets a address and returns it...
}
}