Java web application in a Servlet container vs. standalone

Question

What are the advantages of building a small Java web app to run in a Servlet container (like Tomcat) vs. building a standalone Java app with a built-in web server and runnin

Answer 1

There are 2 separate questions in here:

1. Should I be using an embedded server, or deploy into a container?

   I don't think you should be seeing a big difference one way or the other. There's slightly more code to startup a Jetty server programmatically, and configuration is easier to do programmatically. Even though IDE support for web app configuration and deployment is getting better, it's still worse than for standalone applications (this is kinda by definitions, since there's a superset of things to support).

   On the other hand, app servers give you some nice benefits like built-in management, built-in ability to run as a service, etc.

   You could even use a hybrid approach: use an embedded server to develop locally, then deploy into a container in production. But that's a bit weird: if you go through the trouble of making a proper WAR file, IDEs should really be able to handle deployment into a container adequately.

   BTW, it's weird that you have issues with hot-redeploy; Tomcat shouldn't be having issues with it unless you're running into some strange corner case...

2. Should I be using Servlet API?

   This is orthogonal from #1. You could very well embed Jetty and implement Servlets. You could also use Restlet API inside Tomcat through a ServerServlet http://www.restlet.org/documentation/1.0/faq#02.

   I personally find the Servlet API to be pretty straight-forward.You get nice things like concurrency and state management. I don't quite know what that means that RESTful design is not supported, but if Restlets address your requirements better, then use that...