You'll probably have to know a little bit about Java, Ant, and build files for this sample
build.xml file to be any use to you, but if you're looking for a sample Ant build script that can be used to create a
war file, or one that simple uses a
war task, this example might work for you.
I'm not going to provide any explanation of any of this right now, but if I have time in the future I'll come back here and add a few comments about how this build script works.