How to initialize the common connection before any Servlet / JSP will be accessed ?

Scenario

I need to initialize the common connection before any servlet / jsp will be accessed.

Solution

Make the connection in a context listener and save it.

Example

public class MyServletContextListener implements ServletContextListener {

  public void contextInitialized(ServletContextEvent event) {

     ServletContext sc = event.getServletContext();

     // Make connection and put connection object in servlet context

  }

  public void contextDestroyed(ServletContextEvent event) {

     // Clean up code here

  }

}