Java Web Service with backend stuff going on..

Question

Hi Everyone,

I'm thinking about developing a Java Web Service using RESTEasy. I am going to follow this example: http://technicalmumbojumbo.wordpress.com/2009/10/13/restful-webservices-using-jboss-resteasy-tutorial/

Now, that's very well and good for getting the server to reply back with a simple response, however how do I get some "backend" things going on? For example, I want a queuing system running in the background constantly on the server, processing objects in the queue. When someone accesses a certain URL (The web service), i want the web service to Enqueue something..

The only thing I can think of in my head at the minute, which is probably totally wrong, is to make a seperate Java (J2SE) application, which runs the Queue, and connect the Web Service to it via RMI or Cajo or something..

I guess what I'm asking is that does a Java Web App running on Tomcat have any concept of a "main() method" which gets executed on server startup?

Any help is appreciated

Thanks

Answer 1

I guess what I'm asking is that does a Java Web App running on Tomcat have any concept of a "main() method" which gets executed on server startup?

You can have a servlet get kick started on the load of the application using the appropriate load-on-startup tag in the web.xml file.

So for example:

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns="http://java.sun.com/xml/ns/j2ee"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd"
    version="2.4">

<!-- snip stuff -->

    <servlet>
        <servlet-name>context</servlet-name>
        <servlet-class>org.lastname.firstname.YourStartupServlet</servlet-class>
        <load-on-startup>1</load-on-startup>
    </servlet>

<!-- snip stuff -->

</web-app>