11d24e6844
FileSnapshot.isModified may have reported a file to be clean although it was actually dirty. Imagine you have a FileSnapshot on file f. lastmodified and lastread are both t0. Now time is t1 and you 1) modify the file 2) update the FileSnapshot of the file (lastModified=t1, lastRead=t1) 3) modify the file again 4) wait 3 seconds 5) ask the Filesnapshot whether the file is dirty or not. It erroneously answered it's clean. Any file which has been modified longer than 2.5 seconds ago was reported to be clean. As the test shows that's not always correct. The real-world problem fixed by this change is the following: * A gerrit server using JGit to serve git repositories is processing fetch requests while simultaneously a native git garbage collection runs on the repo. * At time t1 native git writes temporary files in the pack folder setting the mtime of the pack folder to t1. * A fetch request causes JGit to search for new packfiles and JGit remembers this scan in a Filesnapshot on the packs folder. Since the gc is not finished JGit doesn't see any new packfiles. * The fetch is processed and the gc ends while the filesystem timer is still t1. GC writes a new packfile and deletes the old packfile. * 3 seconds later another request arrives. JGit does not yet know about the new packfile but is also not rescanning the pack folder because it cached that the last scan happened at time t1 and pack folder's mtime is also t1. Now JGit will not be able to resolve any object contained in this new pack. This behavior may be persistent if objects referenced by the ref/meta/config branch are affected so gerrit can't read permissions stored in the refs/meta/config branch anymore and will not allow any pushes anymore. The pack folder will not change its mtime and therefore no rescan will take place. Change-Id: I3efd0ccffeb97b01207dc3e7a6b85c6b06928fad Signed-off-by: Matthias Sohn <matthias.sohn@sap.com> |
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.mvn | ||
lib | ||
org.eclipse.jgit | ||
org.eclipse.jgit.ant | ||
org.eclipse.jgit.ant.test | ||
org.eclipse.jgit.archive | ||
org.eclipse.jgit.http.apache | ||
org.eclipse.jgit.http.server | ||
org.eclipse.jgit.http.test | ||
org.eclipse.jgit.junit | ||
org.eclipse.jgit.junit.http | ||
org.eclipse.jgit.lfs | ||
org.eclipse.jgit.lfs.server | ||
org.eclipse.jgit.lfs.server.test | ||
org.eclipse.jgit.lfs.test | ||
org.eclipse.jgit.packaging | ||
org.eclipse.jgit.pgm | ||
org.eclipse.jgit.pgm.test | ||
org.eclipse.jgit.test | ||
org.eclipse.jgit.ui | ||
tools | ||
.buckconfig | ||
.buckversion | ||
.gitattributes | ||
.gitignore | ||
.mailmap | ||
BUCK | ||
CONTRIBUTING.md | ||
LICENSE | ||
README.md | ||
pom.xml |
README.md
Java Git
An implementation of the Git version control system in pure Java.
This package is licensed under the EDL (Eclipse Distribution License).
JGit can be imported straight into Eclipse, built and tested from there, but the automated builds use Maven.
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org.eclipse.jgit
A pure Java library capable of being run standalone, with no additional support libraries. It provides classes to read and write a Git repository and operate on a working directory.
All portions of JGit are covered by the EDL. Absolutely no GPL, LGPL or EPL contributions are accepted within this package.
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org.eclipse.jgit.ant
Ant tasks based on JGit.
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org.eclipse.jgit.archive
Support for exporting to various archive formats (zip etc).
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org.eclipse.jgit.http.apache
Apache httpclient support
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org.eclipse.jgit.http.server
Server for the smart and dumb Git HTTP protocol.
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org.eclipse.jgit.pgm
Command-line interface Git commands implemented using JGit ("pgm" stands for program).
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org.eclipse.jgit.packaging
Production of Eclipse features and p2 repository for JGit. See the JGit Wiki on why and how to use this module.
Tests
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org.eclipse.jgit.junit
Helpers for unit testing
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org.eclipse.jgit.test
Unit tests for org.eclipse.jgit
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org.eclipse.jgit.ant.test
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org.eclipse.jgit.pgm.test
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org.eclipse.jgit.http.test
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org.eclipse.jgit.junit.test
No further description needed
Warnings/Caveats
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Native smbolic links are supported, provided the file system supports them. For Windows you must have Windows Vista/Windows 2008 or newer, use a non-administrator account and have the SeCreateSymbolicLinkPrivilege.
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Only the timestamp of the index is used by jgit if the index is dirty.
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JGit requires at least a Java 7 JDK.
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CRLF conversion is performed depending on the core.autocrlf setting, however Git for Windows by default stores that setting during installation in the "system wide" configuration file. If Git is not installed, use the global or repository configuration for the core.autocrlf setting.
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The system wide configuration file is located relative to where C Git is installed. Make sure Git can be found via the PATH environment variable. When installing Git for Windows check the "Run Git from the Windows Command Prompt" option. There are other options like Eclipse settings that can be used for pointing out where C Git is installed. Modifying PATH is the recommended option if C Git is installed.
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We try to use the same notation of $HOME as C Git does. On Windows this is often not the same value as the user.home system property.
Package Features
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org.eclipse.jgit/
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Read loose and packed commits, trees, blobs, including deltafied objects.
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Read objects from shared repositories
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Write loose commits, trees, blobs.
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Write blobs from local files or Java InputStreams.
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Read blobs as Java InputStreams.
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Copy trees to local directory, or local directory to a tree.
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Lazily loads objects as necessary.
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Read and write .git/config files.
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Create a new repository.
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Read and write refs, including walking through symrefs.
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Read, update and write the Git index.
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Checkout in dirty working directory if trivial.
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Walk the history from a given set of commits looking for commits introducing changes in files under a specified path.
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Object transport Fetch via ssh, git, http, Amazon S3 and bundles. Push via ssh, git and Amazon S3. JGit does not yet deltify the pushed packs so they may be a lot larger than C Git packs.
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Garbage collection
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Merge
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Rebase
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And much more
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org.eclipse.jgit.pgm/
- Assorted set of command line utilities. Mostly for ad-hoc testing of jgit log, glog, fetch etc.
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org.eclipse.jgit.ant/
- Ant tasks
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org.eclipse.jgit.archive/
- Support for Zip/Tar and other formats
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org.eclipse.http.*/
- HTTP client and server support
Missing Features
There are some missing features:
- gitattributes support
Support
Post question, comments or patches to the jgit-dev@eclipse.org mailing list. You need to be subscribed to post, see here:
https://dev.eclipse.org/mailman/listinfo/jgit-dev
Contributing
See the EGit Contributor Guide:
http://wiki.eclipse.org/EGit/Contributor_Guide
About Git
More information about Git, its repository format, and the canonical C based implementation can be obtained from the Git website: