Build app from .WAR source file?

I have a .WAR file. This file store an app created by Vaadin. I want to export it to a complete app for using. So, how can I do it?

I’m not quite sure I understood you correctly, but I’ll give a try.

If you have a WAR which includes sources for the application, you should in e.g. Eclipse be able to import this as an existing project from WAR file. You might also have to enable the Vaadin project facade under project properties if it’s not recognized by the Vaadin plugin.

From there on you can edit source and deploy as a regular web application project like any other project.

Was this even close to what you were asking for?

I found a WAR package on the Internet. The package contains a web-based application. I used Eclipse to import it (with Vaadin plugins) and export it to a JAR file. Now, how can I open this JAR file in a web browser?

Hello Tin Tinh,
if you use Tomcat, you should pack your JAR into a WAR and deploy it on your server.

Which version of Eclipse includes the Tomcat server? In Eclipse, when I go to “Windows > Preferences > Servers > Runtime Environments” and click “Add” button, but there’s nothing to choose. So I think that my Eclipse version doesn’t have Tomcat server.
Can you give me the link of Eclipse includes Tomcat server?

You need to download Tomcat separately and install it somewhere. After that you open up Eclipse, go to Servers view (tab) and right-click → new → server. Choose apache Tomcat and provide the directory where you installed your downloaded Tomcat.
After that you can drag the eclipse project which has been imported on top of the Apache Tomcat server in the Servers view. Now when you start you server for Runing or Debuggin it shoudl deploy your project to that server also.

If it’s a working WAR application it should work like that out of the box. Usually the URL will be http://localhost:8080/projectName, but this kind of depends on the configuration.