I wrote some Groovy code, and I'd like to integrate it with the existing Java code. We'd like to be able to keep our ant scripts, and only add the needed Groovy functionality. Will Gant allow us to keep our existing scripts?
According to the Gant site, no:
A Gant build script uses Groovy script, not XML, but it uses the Ant tasks. Therefore if you have any custom Ant tasks you will still be able to use those.
Perhaps you could give more detail about what you want to do. You can call normal Ant scripts from Gant and vice-versa.
You can also use the groovy ant task to run arbitrary Groovy in your normal (or Gant-flavored) ant builds.
The following doesn't answer the question with respect to Gant, but it might help with the problem:
Gradle is a Groovy-build tool. It is more sophisticated than Gant. I've blogged on this here.
From the Gradle FAQ (here):
Gradle can import any Ant build script. Gradle integrates deeply with an Ant build. Every Ant target is represented as a Gradle task. This task can be further enhanced in your Gradle build script.