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Bug 318875

Summary:	IOException "Unknown repository format "null"; expected "0""
Product:	[Technology] EGit	Reporter:	Matthias Sohn <matthias.sohn>
Component:	Core	Assignee:	Mathias Kinzler <mathias.kinzler>
Status:	CLOSED FIXED	QA Contact:
Severity:	normal
Priority:	P3	CC:	dmitry.neverov, jens.happe, markward.schubert, robin, stefan.lay, z0wkh2102
Version:	0.9.0
Target Milestone:	---
Hardware:	PC
OS:	Windows XP
Whiteboard:

Description Matthias Sohn

2010-07-05 07:16:23 EDT

I found this stacktrace in my console using
egit 97154e8 and jgit 629fd0d :

java.io.IOException: Unknown repository format "null"; expected "0".
	at org.eclipse.jgit.lib.Repository.<init>(Repository.java:297)
	at org.eclipse.jgit.lib.Repository.<init>(Repository.java:190)
	at org.eclipse.jgit.lib.Repository.<init>(Repository.java:138)
	at org.eclipse.egit.core.RepositoryCache.lookupRepository(RepositoryCache.java:51)
	at org.eclipse.egit.ui.internal.repository.RepositoriesView$6.run(RepositoriesView.java:393)
	at org.eclipse.core.internal.jobs.Worker.run(Worker.java:54)

Comment 1 Stefan Lay

2010-12-01 03:19:35 EST

I also have this exception. The reason was that my config file in the .git folder was suddenly empty.

JGit expects a key core.repositoryformatversion=0 in the config file.

Maybe one could present a better error message, or even repair the config file in such a case?

Comment 2 Mathias Kinzler

2011-01-26 08:16:39 EST

I haven't seen this in quite some time now. If the problem is caused by a "disappearing" config file, we shouldn't hide this Exception anyway.
Should this comes up again, let's reopen this bug.

Comment 3 Matthias Sohn

2011-02-10 07:25:01 EST

fixed with http://egit.eclipse.org/r/#change,2474
merged as 84d9259d621842a36d3bc0c583cd43b0bcbd6fe3

Comment 4 Jens Happe

2011-07-07 05:55:22 EDT

I just had the same problem using Eclipse JGit 1.0.0.201106090707-r	

I edited my repository using gitk (I only created a new branch in "Repository->Visualize All Branch History") while Eclipse was running in the background. After that my repository simply disappeared from the RepositoriesView. The Eclipse error log contained the entry below. The config file in the .git folder was empty (same as for Stefan).

An Exception occurred while looking up the Repository path "C:\Some\Path\.git"; it will be removed from the Git Repositories View

java.io.IOException: Unknown repository format "null"; expected "0".
  at org.eclipse.jgit.storage.file.FileRepository.<init>(FileRepository.java:185)
  at org.eclipse.jgit.storage.file.FileRepository.<init>(FileRepository.java:128)
  at org.eclipse.egit.core.RepositoryCache.lookupRepository(RepositoryCache.java:52)
  at org.eclipse.egit.ui.internal.repository.RepositoriesView.initRepositoriesAndListeners(RepositoriesView.java:279)
  at org.eclipse.egit.ui.internal.repository.RepositoriesView.access$6(RepositoriesView.java:271)
  at org.eclipse.egit.ui.internal.repository.RepositoriesView$8.run(RepositoriesView.java:439)
  at org.eclipse.core.internal.jobs.Worker.run(Worker.java:54)

Comment 5 Mathias Kinzler

2011-07-07 06:26:45 EDT

Seems this is back...

Comment 6 Dmitry Neverov

2011-07-07 06:36:10 EDT

I get this error after starting using a org.eclipse.egit.core.RepositoryCache. Our code never delete repositories, so IMHO bug is somewhere in RepositoryCache.

Comment 7 Robin Stocker

2013-09-27 11:32:15 EDT

I've not seen this in a long time, please reopen in case this happens again.