Generating Java sources with an Ant script using Maven

Question

I need to generate some Java sources that will then be compiled by Maven. The problem is the legacy code that generates those sources is written in Java. The solution (work-around) used was to have:

• project A with the code that generates Java sources
• project B that depends on project A and calls antrun in Maven to execute the classes in project A

What happens when you build project B is that Maven will:

• compile project A (code that generates sources) and do whatever else the pom.xml of project A tells it to do.
• antrun those classes (as requested by the pom.xml of project B) - thus sources will get generated and added to project B
• compile project B sources

This because Antrun requires the classes in project A to already be compiled when it's executed. This is however an ugly solution, and project A and B should actually be just one project. I know I should use:

<phase>generate-sources</phase>

and I saw an example with Groovy (http://blog.retep.org/2009/11/07/using-groovy-to-generate-java-sources-in-maven/), but I would like to know if there's any simpler way to do this while having everything in one project and not having to change the code-generation from Java to groovy or something else.

Thanks.

Answer 1

I use Groovy for situations like that, but if you don't want to, then having two separate projects is the correct thing to do.

And I would not compile one project from the other, I would just leave them as separate projects. Usually the code generator project won't change as often as the "real" project, so there's no need to build it all the time.