How can I write custom servlet context init method

Question

I wish to set up a few application wide variables with servletContext.setAttributes on servlet context initialization phase .How can I achieve this.

Answer 1

Implement javax.servlet.SevletContextListener which gets a callback when javax.servlet.ServletContext is initialized.

Here is the example:

public class MyServletContextListener implements ServletContextListener
{
   public void contextInitialized(ServletContextEvent sce)
   {
       ServletContext sc = sce.getServletContext();
       //do your initialization here.
       sc.setAttribute(.....);
   }

   public void contextDestroyed(ServletContextEvent sce)
   {
       ServletContext sc = sce.getServletContext();
       //do your cleanup here

   }
}