Targetplatform and running

In my understand gradle "out-of-the-box" does not support PDE projects. Hence an 'eclipse' gradle project does not know about the target platform.

In my project build, i have several eclipse plugins and a directory with the target platform files.

platform/plugins/*.jar

1.
prj1, has a trgdef.target file, which is an Eclipse target platform definition.
Can i use it to make this targetplatform be a p2 or maven thing? Or can i make the directory directly a p2? No downloads shall take place, only the contained files and the project (like 'prj1' 'prj2' shall exist for the build)

2.
prj2, references prj1 and is a osgi console application.
Can i build it and run it in the build?