The train from Danang to Hue is a beautiful ride mainly along the coastline. Takes about 3 hours. Sit on the right side of the train if you can. As for which is best Hoi An or Hue well that depends on what you are looking for. Hoi An is very intersting in the Ancient town and if you are wanting to have clothes made up then that is a good place to stay.
Apache Tomcat, often referred to as Tomcat, is an open-source web server developed by the Apache Software Foundation (ASF).
The web.xml Deployment Descriptor file describes how to deploy a web application in a servlet container such as Tomcat. This file is required for every application you deploy on Tomcat.