jgit clone

gistfile1.txt

    public void cloneRepository(Project originalProject, Project forkingProject) throws GitAPIException, IOException {
        String url = // original project's git url
        String directory = "repo/git/" + forkingProject.owner + "/" + forkingProject.name;
        Git.cloneRepository()
            .setURI(url)
            .setDirectory(new File(directory))
            .setCloneAllBranches(true)
            .call();
        forkingProject.repositoryUrl = directory + "/.git";
    }