code: public void cloneNoCheckout(boolean withProgress) throws Exception {
          CloneCommand clone = Git.cloneRepository().setURI(repositoryUrl).setDirectory(localRepo.getDirectory().getParentFile()).setNoCheckout(true);
          // https://bugs.eclipse.org/bugs/show_bug.cgi?id=442029
          if (credentialsProvider != null)
              clone.setCredentialsProvider(credentialsProvider);
          if (withProgress)
              clone.setProgressMonitor(new TextProgressMonitor(new PrintWriter(System.out)));
          clone.call();
      }
docs: In lieu of sparse checkout since it's not yet supported in JGit:
  https://bugs.eclipse.org/bugs/show_bug.cgi?id=383772