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I've come up with a solution that I have used over the years that is container independent for applications deployed in WebLogic, JBoss and Tomcat. It's not really rocket science, but I use a Servlet as my startup and shutdown class by taking advantage of the servlet lifecycle and the init() and destroy() methods.

Most web containers will create an instance of the servlet by calling the no-args constructor. Once the instance is created, the container will then call the Servlet's init() method. The init() method is guaranteed to be called only once during the Servlet's lifecycle which makes it use as a startup class work perfectly. The same goes for the destroy() method, which is also guaranteed to be called only once and that makes it an ideal candidate as a shutdown class.

To load the servlet on deployment or server start-up, just enable the load-on-startup attribute of the servlet. Here's what the web.xml looks like for the startup servlet:

<?xml version="1.0" encoding="ISO-8859-1"?>

<!DOCTYPE web-app 
    PUBLIC "-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN" 
    "http://java.sun.com/dtd/web-app_2_3.dtd"> 
 
<web-app> 
 
    <servlet> 
        <servlet-name>startupServlet</servlet-name>
        <servlet-class>com.j2eegeek.servlet.util.StartupServlet</servlet-class> 
        <load-on-startup>9</load-on-startup> 
    </servlet> 
 
    <servlet-mapping> 
        <servlet-name>startupServlet</servlet-name> 
        <url-pattern>/startupServlet</url-pattern> 
    </servlet-mapping> 
 
</web-app>