I am using JGit to do some manipulation of a repo.

Is there an easy way for me to be sure that a repo is/isn't in a detached head state?

The best I've come up with so far is to use Repository.getBranch(), which will return the proper branch name if we're not detached, and an SHA-1 if we're detached.

I can test the return for 40 hex characters, and I admit that the odds of a legitimate branch name being 40 hex characters long are vanishingly small. But I wonder if there's some dead-simple way to do this that I just can't find in the docs.

I am using JGit to do some manipulation of a repo.

Is there an easy way for me to be sure that a repo is/isn't in a detached head state?

The best I've come up with so far is to use Repository.getBranch(), which will return the proper branch name if we're not detached, and an SHA-1 if we're detached.

I can test the return for 40 hex characters, and I admit that the odds of a legitimate branch name being 40 hex characters long are vanishingly small. But I wonder if there's some dead-simple way to do this that I just can't find in the docs.

• jgit

Share Improve this question Follow edited Mar 27 at 18:31 jonrsharpe 122k3030 gold badges268268 silver badges475475 bronze badges asked Mar 27 at 18:29 GeePawHillGeePawHill 2311 silver badge77 bronze badges 2

• I think this is answered here: stackoverflow/questions/24992843/… (if the returned string doesn't start with 'refs/', HEAD points to a commit or nowhere. – Rüdiger Herrmann Commented Mar 27 at 22:21
• Thanks, Rudiger, that was just the clue I needed. – GeePawHill Commented Mar 28 at 17:37

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1 Answer 1

Sorted by: Reset to default 0

As Rudiger suggested, the answer is straightforward.

Instead of using repo.getBranch() to get the branch name, use repo.getFullBranch() to get it.

The full-branch version returns a string "refs/heads/[branchname]" if we're on a branch, or a raw SHA-1 if we are not.

Confirmed, tested, and pushed.

Thanks!