I am using http://github-api.kohsuke.org/ to receive a pushEvent and getting the corresponding PullRequest.
Now I want to commit the changes from that PushEvent to other branches(not just the one the PullRequest was for). Is that somehow possible?
I already checked out the GHContentBuilder-class but I would need the changed files for that (can get the names from the PullRequest but not the whole files).
Is it possible to forward the PullRequest to another branch or is there some possibility with the PushEvent?
There isn't a one-step general-case process for doing what you want, no, because the two branches may be completely unrelated or may create merge conflicts that would need to be resolved. If you can give a more concrete example of what exactly you're trying to accomplish, we may be able to point you in the right direction.
Let us know!