VCDIFF for Java or alternative binary diff formats

Question

Is there an open-source Java implementation of the VCDIFF binary diff format (decoder and encoder)?

There are xdelta and open-vcdiff, but those are both C libraries.

Alternatively, are the other formats/algorithms that one could use to generate diffs for binary files from Java?

score 4 · Answer 1 · answered Sep 08 '13 at 20:08

You can generate binary diffs using badiff; the website is

and it is available on maven central. It's BSD licensed, so friendly for both OSS and commercial. The algorithm used is a chunked version of the O(ND) diff described in this paper:

http://www.xmailserver.org/diff2.pdf

The diff format isn't particularly compatible with anything else, but it produces some really good and really small diffs.

The library is pretty fast; on my desktop machine it can generate a diff for two random 50MB input streams in 54 seconds. Hopefully that's fast enough; I think it's reasonably impressive since that's a comparison of two token streams of 50 million tokens each. badiff will take advantage of multiple CPU cores when computing diffs.

disclaimer: I'm the author of badiff, so of course I think it's cool. I'm always open to suggestions; things like being able to read/write "standard" binary diff formats sound like cool new features to add in upcoming releases.

I've fixed some nasty bugs in the diff computation pipeline, so please use version 1.0.5 stable or higher. Sorry for the inconvenience. — esialb, Sep 11 '13 at 06:33
Website broken? Can you please host it somewhere permanent like GitHub? — Aleksandr Dubinsky, Feb 12 '16 at 19:27

score 3 · Answer 2 · answered Jul 10 '09 at 07:07

I have a decoder for VCDIFF written in C#, which would probably be fairly straightforward to port to Java, if that's any help. It's part of MiscUtil but I don't think it relies on any other bits of MiscUtil (or only minimally, anyway).

Unfortunately I never got round to writing an encoder, which is obviously rather harder - and wasn't necessary in our case (where we needed to apply patches in .NET on a mobile device, but could create them however we wanted at the server).

Actually, I am in a similar situation, so having just the decoder would probably work. I'll take a look at MiscUtil, thanks. — Thilo, Jul 10 '09 at 07:29

score 3 · Answer 3 · edited Feb 25 '14 at 06:43

3

I hava ported MiscUtil's vcdiff decoder to java. https://github.com/xiaxiaocao/jvcdiff update: now it also have a vcdiff encoder

edited Feb 25 '14 at 06:43

Dong Liu

43
4

answered Dec 16 '12 at 08:49

Hsiafan

197
1
7

Did you take it down? – Aleksandr Dubinsky Feb 12 '16 at 19:23
Some seems to have cloned the decoder here: https://github.com/keremkusmezer/jvcdiff – Aleksandr Dubinsky Feb 12 '16 at 19:26

David Ehrmann · Answer 4 · 2016-08-14T05:44:19.283

1

I have a Java port of open-vcdiff on Github. It's tested against open-vcdiff, but it's not used in production anywhere.

edited Aug 14 '16 at 05:44

answered May 04 '12 at 03:50

David Ehrmann

7,366
2
31
40

score 1 · Answer 5 · answered Jul 16 '09 at 14:18

1

There is a java-port of xdelta: http://sourceforge.net/projects/javaxdelta/

But i can not say anything on its quality - i did not try it yet.

answered Jul 16 '09 at 14:18

I think it does not do VCDIFF, but GDIFF, which is an older standard (and MUCH simpler). It does have both decoder and encoder, though. – Thilo Jul 16 '09 at 23:03
javaxdelta works fine, we are using it for directory diffs (with [this wrapper](https://github.com/alexkasko/delta-updater)) in production – alexkasko Oct 27 '12 at 12:03

VCDIFF for Java or alternative binary diff formats

5 Answers5