code: public void deleteBranch(Ref branch, boolean forceDelete) 
      throws IOException, JavaGitException {
      GitBranch gitBranch = new GitBranch();
      gitBranch.deleteBranch(path, forceDelete, false, branch);
      branch = null;
    }
docs: Deletes a branch
  
  @param branch
  The branch to delete
  @param forceDelete
  True if force delete option -D should be used,
  false if -d should be used.
  @throws IOException
  Thrown in case of I/O operation failure
  @throws JavaGitException
  Thrown when there is an error executing git-branch.