Question

Is there a way to programmatically download a single file from a remote git repository, in Java?

1. I prefer a solution which uses as little bandwidth as possible, preferably only downloading that single file. I do not need to browse the repository, I already have the file’s path.
2. I prefer a solution which does not depend on other applications (e.g. an installation of another git client on the machine). A Java library which contains a git client implementation itself would be optimal.

I was able to do something similar with Subversion using SVNKit and I’ve seen there is a pure java implementation of git (eclipse’s JGit) which might be able to do something similar, so I hope there is a positive answer; though from what I understand about how git works – allowing updates only from local repositories – this could prove to be problematic.

Answer 1

git isn’t really designed for single file access from a remote repository but you can abuse git archive for this. The downside is that you have to download a “tree” rather than just the blob that you need.

E.g.

git archive --remote=url://to.git.repo branch path/to/dir | tar -x file

As an alternative, if you have gitweb set up on the remote repository you can use a simple curl or wget command to download any file in its “raw” format.