Want an eclipse java project to run ant build files automatically

I have an Eclipse Java project, not a plugin project. And the project has some external dependencies that I handle in two separate ant files. Everything works fine, but I want to force Eclipse to run the ant files everytime it builds my project.

How can I do that?

If this had been a plugin project I would have handled it in a customBuildCallbacks.xml and included it in my build.properties, but doesnt seem to work when its just a java project