Question

I have web application deployed in apache tomcat server and I need to start another console application (socket server) after primary web app was deployed. This socket server in the same WAR file as the primary app and has access to all beans and classes of web application.

I need to start it after starting tomcat with deployed web application (not after opening index page of app or something else)

How can I do that?

Answer 1

You need to implement ServletContextListner interface

public class MyServletContextListener implements ServletContextListener {

    @Override
    public void contextDestroyed(ServletContextEvent arg0) {
    //Notification that the servlet context is about to be shut down.   
    }

    @Override
    public void contextInitialized(ServletContextEvent arg0) {
    // do all the tasks that you need to perform just after the server starts

    //Notification that the web application initialization process is starting
    }

}

And configure it in your deployment descriptor web.xml

<listener>
    <listener-class>
        mypackage.MyServletContextListener
    </listener-class>
</listener>