org.eclipse.jgit.internal.storage.file

Class GC

java.lang.Object

org.eclipse.jgit.internal.storage.file.GC

public class GC
extends Object

A garbage collector for git FileRepository. Instances of this class are not thread-safe. Don't use the same instance from multiple threads. This class started as a copy of DfsGarbageCollector from Shawn O. Pearce adapted to FileRepositories.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
class	GC.RepoStatistics A class holding statistical data for a FileRepository regarding how many objects are stored as loose or packed objects

Constructor Summary

Constructors

Constructor and Description
GC(FileRepository repo) Creates a new garbage collector with default values.

Method Summary

Methods

Modifier and Type	Method and Description
Collection<PackFile>	gc() Runs a garbage collector on a FileRepository.
GC.RepoStatistics	getStatistics() Returns the number of objects stored in pack files.
void	packRefs() Packs all non-symbolic, loose refs into packed-refs.
void	prune(Set<ObjectId> objectsToKeep) Like "git prune" this method tries to prune all loose objects which are unreferenced.
void	prunePacked() Like "git prune-packed" this method tries to prune all loose objects which can be found in packs.
Collection<PackFile>	repack() Packs all objects which reachable from any of the heads into one pack file.
void	setExpire(Date expire) During gc() or prune() each unreferenced, loose object which has been created or modified after or at expire will not be pruned.
void	setExpireAgeMillis(long expireAgeMillis) During gc() or prune() each unreferenced, loose object which has been created or modified in the last expireAgeMillis milliseconds will not be pruned.
GC	setProgressMonitor(ProgressMonitor pm) Set the progress monitor used for garbage collection methods.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

GC

public GC(FileRepository repo)

Creates a new garbage collector with default values. An expirationTime of two weeks and null as progress monitor will be used.

Parameters:

repo - the repo to work on

Method Detail

gc

public Collection<PackFile> gc()
                        throws IOException,
                               ParseException

Runs a garbage collector on a FileRepository. It will

• pack loose references into packed-refs
• repack all reachable objects into new pack files and delete the old pack files
• prune all loose objects which are now reachable by packs

Returns:

the collection of PackFile's which are newly created

Throws:

IOException

ParseException - If the configuration parameter "gc.pruneexpire" couldn't be parsed

prunePacked

public void prunePacked()
                 throws IOException

Like "git prune-packed" this method tries to prune all loose objects which can be found in packs. If certain objects can't be pruned (e.g. because the filesystem delete operation fails) this is silently ignored.

Throws:

IOException

prune

public void prune(Set<ObjectId> objectsToKeep)
           throws IOException,
                  ParseException

Like "git prune" this method tries to prune all loose objects which are unreferenced. If certain objects can't be pruned (e.g. because the filesystem delete operation fails) this is silently ignored.

Parameters:

objectsToKeep - a set of objects which should explicitly not be pruned

Throws:

IOException

ParseException - If the configuration parameter "gc.pruneexpire" couldn't be parsed

packRefs

public void packRefs()
              throws IOException

Packs all non-symbolic, loose refs into packed-refs.

Throws:

IOException

repack

public Collection<PackFile> repack()
                            throws IOException

Packs all objects which reachable from any of the heads into one pack file. Additionally all objects which are not reachable from any head but which are reachable from any of the other refs (e.g. tags), special refs (e.g. FETCH_HEAD) or index are packed into a separate pack file. Objects included in pack files which have a .keep file associated are never repacked. All old pack files which existed before are deleted.

Returns:

a collection of the newly created pack files

Throws:

IOException - when during reading of refs, index, packfiles, objects, reflog-entries or during writing to the packfiles IOException occurs

getStatistics

public GC.RepoStatistics getStatistics()
                                throws IOException

Returns the number of objects stored in pack files. If an object is contained in multiple pack files it is counted as often as it occurs.

Returns:

the number of objects stored in pack files

Throws:

IOException

setProgressMonitor

public GC setProgressMonitor(ProgressMonitor pm)

Set the progress monitor used for garbage collection methods.

Parameters:

pm -

Returns:

this

setExpireAgeMillis

public void setExpireAgeMillis(long expireAgeMillis)

During gc() or prune() each unreferenced, loose object which has been created or modified in the last expireAgeMillis milliseconds will not be pruned. Only older objects may be pruned. If set to 0 then every object is a candidate for pruning.

Parameters:

expireAgeMillis - minimal age of objects to be pruned in milliseconds.

setExpire

public void setExpire(Date expire)

During gc() or prune() each unreferenced, loose object which has been created or modified after or at expire will not be pruned. Only older objects may be pruned. If set to null then every object is a candidate for pruning.

Parameters:

expire - instant in time which defines object expiration objects with modification time before this instant are expired objects with modification time newer or equal to this instant are not expired