different WAR files, shared resources

Question

Suppose you have several applications which share the same code and most of the other resources, but have a somewhat different look and feel, some labels change, etc. (think branding). If each web app is to go in its own WAR file, where do you put the shared resources?

I already use the classpath to share classes and property files. But what about javascript and css files? Is the best way to create and deploy one extra WAR file that will serve these shared files to whatever other application requires them?

I also thought of a build script that does some magic and from a common source spews out the (slightly) different WARs, but I don't like it because it just complicates stuff unnecessarily when you need to build/test/run a single application.

Any other tips and tricks would be appreciated.

Answer 1

You can deploy both WARs in the same EAR and put common resources in the EAR. Then put the appropriate dependencies in the manifest of the web apps to link to the jar files in the ear.

Answer 2

A strategy that I have seen used for such product-line like configurations is using WAR overlays when building with maven. You define a common WAR that contains the common stuff and overlay it with those other WARs that contain the specific stuff to generate different WARs for every application. This method is probably most useful if you deploy the WAR-variants on different machines. But I'm not sure whether I can actually recommend this.

Remember to specify the overlays configuration if you actually override stuff, since otherwise the overriding order is not deterministic. It might even change with a maven-war-plugin upgrade. (It did in our case.)