Sometimes it is a good idea to have a look around you even if everything works fine. So far I was used to Ant for building my java applications. Ant is a great tool and like gnu make it is able to do everything you want it to do. You only have to write a proper configuration file…
Maven is on the first look a bit more restrictive because it forces you to follow some conventions given by the chosen type of a project. But if you follow this way you will get much simpler configuration and well structured layout of project files. The project type specific stuff is handled by plugins and there are plenty of plugins already out there for nearly every task you could imagine. Due to the fact that you can write your own plugin maven is less restrictive as it seems in the beginning. And for all standard use cases I was really satisfied with the already existing plugins.
Maven is written in java itself and therefore available on every platform java is running. The existing plugins can be retrieved from internet repositories. Even depending jar files you need to build or deploy your project are retrieved automatically. Perfect to build on different machines without the need of installing the jar dependencies on every build machine or blow up your source revision system. Just add it to maven configuration and if something is missing it will be retrieved.
The eager Ant is not dead. It has now a new companion.