Class PackWriter

java.lang.Object
org.eclipse.jgit.internal.storage.pack.PackWriter
All Implemented Interfaces:
AutoCloseable

public class PackWriter extends Object implements AutoCloseable

PackWriter class is responsible for generating pack files from specified set of objects from repository. This implementation produce pack files in format version 2.

Source of objects may be specified in two ways:

  • (usually) by providing sets of interesting and uninteresting objects in repository - all interesting objects and their ancestors except uninteresting objects and their ancestors will be included in pack, or
  • by providing iterator of RevObject specifying exact list and order of objects in pack

Typical usage consists of creating an instance, configuring options, preparing the list of objects by calling preparePack(Iterator) or preparePack(ProgressMonitor, Set, Set), and streaming with writePack(ProgressMonitor, ProgressMonitor, OutputStream). If the pack is being stored as a file the matching index can be written out after writing the pack by writeIndex(OutputStream). An optional bitmap index can be made by calling prepareBitmapIndex(ProgressMonitor) followed by writeBitmapIndex(OutputStream).

Class provide set of configurable options and ProgressMonitor support, as operations may take a long time for big repositories. Deltas searching algorithm is NOT IMPLEMENTED yet - this implementation relies only on deltas and objects reuse.

This class is not thread safe. It is intended to be used in one thread as a single pass to produce one pack. Invoking methods multiple times or out of order is not supported as internal data structures are destroyed during certain phases to save memory when packing large repositories.

  • Field Details

    • PACK_VERSION_GENERATED

      private static final int PACK_VERSION_GENERATED
      See Also:
    • NONE

      public static final Set<ObjectId> NONE
      Empty set of objects for preparePack().
    • instances

      private static final Map<WeakReference<PackWriter>,Boolean> instances
    • instancesIterable

      private static final Iterable<PackWriter> instancesIterable
    • objectsLists

      BlockList<ObjectToPack>[] objectsLists
    • objectsMap

      private ObjectIdOwnerMap<ObjectToPack> objectsMap
    • edgeObjects

      private List<ObjectToPack> edgeObjects
    • haveObjects

      private BitmapIndex.BitmapBuilder haveObjects
    • cachedPacks

      private List<CachedPack> cachedPacks
    • tagTargets

      private Set<ObjectId> tagTargets
    • excludeFromBitmapSelection

      private Set<? extends ObjectId> excludeFromBitmapSelection
    • excludeInPacks

      private ObjectIdSet[] excludeInPacks
    • excludeInPackLast

      private ObjectIdSet excludeInPackLast
    • myDeflater

      private Deflater myDeflater
    • reader

      private final ObjectReader reader
    • reuseSupport

      private final ObjectReuseAsIs reuseSupport
      reader recast to the reuse interface, if it supports it.
    • config

      final PackConfig config
    • stats

      private final PackStatistics.Accumulator stats
    • state

      private final PackWriter.MutableState state
    • selfRef

      private final WeakReference<PackWriter> selfRef
    • typeStats

    • sortedByName

      private List<ObjectToPack> sortedByName
    • packcsum

      private byte[] packcsum
    • deltaBaseAsOffset

      private boolean deltaBaseAsOffset
    • reuseDeltas

      private boolean reuseDeltas
    • reuseDeltaCommits

      private boolean reuseDeltaCommits
    • reuseValidate

      private boolean reuseValidate
    • thin

      private boolean thin
    • useCachedPacks

      private boolean useCachedPacks
    • useBitmaps

      private boolean useBitmaps
    • ignoreMissingUninteresting

      private boolean ignoreMissingUninteresting
    • pruneCurrentObjectList

      private boolean pruneCurrentObjectList
    • shallowPack

      private boolean shallowPack
    • canBuildBitmaps

      private boolean canBuildBitmaps
    • indexDisabled

      private boolean indexDisabled
    • checkSearchForReuseTimeout

      private boolean checkSearchForReuseTimeout
    • searchForReuseTimeout

      private final Duration searchForReuseTimeout
    • searchForReuseStartTimeEpoc

      private long searchForReuseStartTimeEpoc
    • depth

      private int depth
    • unshallowObjects

      private Collection<? extends ObjectId> unshallowObjects
    • writeBitmaps

      private PackBitmapIndexBuilder writeBitmaps
    • crc32

      private CRC32 crc32
    • callback

      private ObjectCountCallback callback
    • filterSpec

      private FilterSpec filterSpec
    • packfileUriConfig

      private PackWriter.PackfileUriConfig packfileUriConfig
  • Constructor Details

  • Method Details

    • getInstances

      public static Iterable<PackWriter> getInstances()
      Get all allocated, non-released PackWriters instances.
      Returns:
      all allocated, non-released PackWriters instances.
    • setObjectCountCallback

      public PackWriter setObjectCountCallback(ObjectCountCallback callback)
      Set the ObjectCountCallback.

      It should be set before calling writePack(ProgressMonitor, ProgressMonitor, OutputStream).

      Parameters:
      callback - the callback to set
      Returns:
      this object for chaining.
    • setClientShallowCommits

      public void setClientShallowCommits(Set<ObjectId> clientShallowCommits)
      Records the set of shallow commits in the client.
      Parameters:
      clientShallowCommits - the shallow commits in the client
    • isDeltaBaseAsOffset

      public boolean isDeltaBaseAsOffset()
      Check whether writer can store delta base as an offset (new style reducing pack size) or should store it as an object id (legacy style, compatible with old readers). Default setting: false
      Returns:
      true if delta base is stored as an offset; false if it is stored as an object id.
    • checkSearchForReuseTimeout

      public void checkSearchForReuseTimeout() throws SearchForReuseTimeout
      Check whether the search for reuse phase is taking too long. This could be the case when the number of objects and pack files is high and the system is under pressure. If that's the case and checkSearchForReuseTimeout is true abort the search.
      Throws:
      SearchForReuseTimeout - if the search for reuse is taking too long.
    • setDeltaBaseAsOffset

      public void setDeltaBaseAsOffset(boolean deltaBaseAsOffset)
      Set writer delta base format. Delta base can be written as an offset in a pack file (new approach reducing file size) or as an object id (legacy approach, compatible with old readers). Default setting: false
      Parameters:
      deltaBaseAsOffset - boolean indicating whether delta base can be stored as an offset.
    • enableSearchForReuseTimeout

      public void enableSearchForReuseTimeout()
      Set the writer to check for long search for reuse, exceeding the timeout. Selecting an object representation can be an expensive operation. It is possible to set a max search for reuse time (see PackConfig#CONFIG_KEY_SEARCH_FOR_REUSE_TIMEOUT for more details). However some operations, i.e.: GC, need to find the best candidate regardless how much time the operation will need to finish. This method enables the search for reuse timeout check, otherwise disabled.
    • isReuseDeltaCommits

      public boolean isReuseDeltaCommits()
      Check if the writer will reuse commits that are already stored as deltas.
      Returns:
      true if the writer would reuse commits stored as deltas, assuming delta reuse is already enabled.
    • setReuseDeltaCommits

      public void setReuseDeltaCommits(boolean reuse)
      Set the writer to reuse existing delta versions of commits.
      Parameters:
      reuse - if true, the writer will reuse any commits stored as deltas. By default the writer does not reuse delta commits.
    • isReuseValidatingObjects

      public boolean isReuseValidatingObjects()
      Check if the writer validates objects before copying them.
      Returns:
      true if validation is enabled; false if the reader will handle object validation as a side-effect of it consuming the output.
    • setReuseValidatingObjects

      public void setReuseValidatingObjects(boolean validate)
      Enable (or disable) object validation during packing.
      Parameters:
      validate - if true the pack writer will validate an object before it is put into the output. This additional validation work may be necessary to avoid propagating corruption from one local pack file to another local pack file.
    • isThin

      public boolean isThin()
      Whether this writer is producing a thin pack.
      Returns:
      true if this writer is producing a thin pack.
    • setThin

      public void setThin(boolean packthin)
      Whether writer may pack objects with delta base object not within set of objects to pack
      Parameters:
      packthin - a boolean indicating whether writer may pack objects with delta base object not within set of objects to pack, but belonging to party repository (uninteresting/boundary) as determined by set; this kind of pack is used only for transport; true - to produce thin pack, false - otherwise.
    • isUseCachedPacks

      public boolean isUseCachedPacks()
      Whether to reuse cached packs.
      Returns:
      true to reuse cached packs. If true index creation isn't available.
    • setUseCachedPacks

      public void setUseCachedPacks(boolean useCached)
      Whether to use cached packs
      Parameters:
      useCached - if set to true and a cached pack is present, it will be appended onto the end of a thin-pack, reducing the amount of working set space and CPU used by PackWriter. Enabling this feature prevents PackWriter from creating an index for the newly created pack, so its only suitable for writing to a network client, where the client will make the index.
    • isUseBitmaps

      public boolean isUseBitmaps()
      Whether to use bitmaps
      Returns:
      true to use bitmaps for ObjectWalks, if available.
    • setUseBitmaps

      public void setUseBitmaps(boolean useBitmaps)
      Whether to use bitmaps
      Parameters:
      useBitmaps - if set to true, bitmaps will be used when preparing a pack.
    • isIndexDisabled

      public boolean isIndexDisabled()
      Whether the index file cannot be created by this PackWriter.
      Returns:
      true if the index file cannot be created by this PackWriter.
    • setIndexDisabled

      public void setIndexDisabled(boolean noIndex)
      Whether to disable creation of the index file.
      Parameters:
      noIndex - true to disable creation of the index file.
    • isIgnoreMissingUninteresting

      public boolean isIgnoreMissingUninteresting()
      Whether to ignore missing uninteresting objects
      Returns:
      true to ignore objects that are uninteresting and also not found on local disk; false to throw a MissingObjectException out of preparePack(ProgressMonitor, Set, Set) if an uninteresting object is not in the source repository. By default, true, permitting gracefully ignoring of uninteresting objects.
    • setIgnoreMissingUninteresting

      public void setIgnoreMissingUninteresting(boolean ignore)
      Whether writer should ignore non existing uninteresting objects
      Parameters:
      ignore - true if writer should ignore non existing uninteresting objects during construction set of objects to pack; false otherwise - non existing uninteresting objects may cause MissingObjectException
    • setTagTargets

      public void setTagTargets(Set<ObjectId> objects)
      Set the tag targets that should be hoisted earlier during packing.

      Callers may put objects into this set before invoking any of the preparePack methods to influence where an annotated tag's target is stored within the resulting pack. Typically these will be clustered together, and hoisted earlier in the file even if they are ancient revisions, allowing readers to find tag targets with better locality.

      Parameters:
      objects - objects that annotated tags point at.
    • setShallowPack

      public void setShallowPack(int depth, Collection<? extends ObjectId> unshallow)
      Configure this pack for a shallow clone.
      Parameters:
      depth - maximum depth of history to return. 1 means return only the "wants".
      unshallow - objects which used to be shallow on the client, but are being extended as part of this fetch
    • setFilterSpec

      public void setFilterSpec(@NonNull FilterSpec filter)
      Parameters:
      filter - the filter which indicates what and what not this writer should include
    • setPackfileUriConfig

      public void setPackfileUriConfig(PackWriter.PackfileUriConfig config)
      Parameters:
      config - configuration related to packfile URIs
      Since:
      5.5
    • getObjectCount

      public long getObjectCount() throws IOException
      Returns objects number in a pack file that was created by this writer.
      Returns:
      number of objects in pack.
      Throws:
      IOException - a cached pack cannot supply its object count.
    • getUnoffloadedObjectCount

      private long getUnoffloadedObjectCount() throws IOException
      Throws:
      IOException
    • getObjectSet

      public ObjectIdOwnerMap<ObjectIdOwnerMap.Entry> getObjectSet() throws IOException
      Returns the object ids in the pack file that was created by this writer.

      This method can only be invoked after writePack(ProgressMonitor, ProgressMonitor, OutputStream) has been invoked and completed successfully.

      Returns:
      set of objects in pack.
      Throws:
      IOException - a cached pack cannot supply its object ids.
    • excludeObjects

      public void excludeObjects(ObjectIdSet idx)
      Add a pack index whose contents should be excluded from the result.
      Parameters:
      idx - objects in this index will not be in the output pack.
    • preparePack

      public void preparePack(@NonNull Iterator<RevObject> objectsSource) throws IOException
      Prepare the list of objects to be written to the pack stream.

      Iterator exactly determines which objects are included in a pack and order they appear in pack (except that objects order by type is not needed at input). This order should conform general rules of ordering objects in git - by recency and path (type and delta-base first is internally secured) and responsibility for guaranteeing this order is on a caller side. Iterator must return each id of object to write exactly once.

      Parameters:
      objectsSource - iterator of object to store in a pack; order of objects within each type is important, ordering by type is not needed; allowed types for objects are Constants.OBJ_COMMIT, Constants.OBJ_TREE, Constants.OBJ_BLOB and Constants.OBJ_TAG; objects returned by iterator may be later reused by caller as object id and type are internally copied in each iteration.
      Throws:
      IOException - when some I/O problem occur during reading objects.
    • preparePack

      public void preparePack(Collection<? extends CachedPack> c)
      Prepare the list of objects to be written to the pack stream.

      PackWriter will concat and write out the specified packs as-is.

      Parameters:
      c - cached packs to be written.
    • preparePack

      public void preparePack(ProgressMonitor countingMonitor, @NonNull Set<? extends ObjectId> want, @NonNull Set<? extends ObjectId> have) throws IOException
      Prepare the list of objects to be written to the pack stream.

      Basing on these 2 sets, another set of objects to put in a pack file is created: this set consists of all objects reachable (ancestors) from interesting objects, except uninteresting objects and their ancestors. This method uses class ObjectWalk extensively to find out that appropriate set of output objects and their optimal order in output pack. Order is consistent with general git in-pack rules: sort by object type, recency, path and delta-base first.

      Parameters:
      countingMonitor - progress during object enumeration.
      want - collection of objects to be marked as interesting (start points of graph traversal). Must not be null.
      have - collection of objects to be marked as uninteresting (end points of graph traversal). Pass NONE if all objects reachable from want are desired, such as when serving a clone.
      Throws:
      IOException - when some I/O problem occur during reading objects.
    • preparePack

      public void preparePack(ProgressMonitor countingMonitor, @NonNull Set<? extends ObjectId> want, @NonNull Set<? extends ObjectId> have, @NonNull Set<? extends ObjectId> shallow) throws IOException
      Prepare the list of objects to be written to the pack stream.

      Like preparePack(ProgressMonitor, Set, Set) but also allows specifying commits that should not be walked past ("shallow" commits). The caller is responsible for filtering out commits that should not be shallow any more ("unshallow" commits as in setShallowPack(int, java.util.Collection<? extends org.eclipse.jgit.lib.ObjectId>)) from the shallow set.

      Parameters:
      countingMonitor - progress during object enumeration.
      want - objects of interest, ancestors of which will be included in the pack. Must not be null.
      have - objects whose ancestors (up to and including shallow commits) do not need to be included in the pack because they are already available from elsewhere. Must not be null.
      shallow - commits indicating the boundary of the history marked with have. Shallow commits have parents but those parents are considered not to be already available. Parents of shallow commits and earlier generations will be included in the pack if requested by want. Must not be null.
      Throws:
      IOException - an I/O problem occurred while reading objects.
    • preparePack

      public void preparePack(ProgressMonitor countingMonitor, @NonNull Set<? extends ObjectId> want, @NonNull Set<? extends ObjectId> have, @NonNull Set<? extends ObjectId> shallow, @NonNull Set<? extends ObjectId> noBitmaps) throws IOException
      Prepare the list of objects to be written to the pack stream.

      Like preparePack(ProgressMonitor, Set, Set) but also allows specifying commits that should not be walked past ("shallow" commits). The caller is responsible for filtering out commits that should not be shallow any more ("unshallow" commits as in setShallowPack(int, java.util.Collection<? extends org.eclipse.jgit.lib.ObjectId>)) from the shallow set.

      Parameters:
      countingMonitor - progress during object enumeration.
      want - objects of interest, ancestors of which will be included in the pack. Must not be null.
      have - objects whose ancestors (up to and including shallow commits) do not need to be included in the pack because they are already available from elsewhere. Must not be null.
      shallow - commits indicating the boundary of the history marked with have. Shallow commits have parents but those parents are considered not to be already available. Parents of shallow commits and earlier generations will be included in the pack if requested by want. Must not be null.
      noBitmaps - collection of objects to be excluded from bitmap commit selection.
      Throws:
      IOException - an I/O problem occurred while reading objects.
    • getObjectWalk

      private ObjectWalk getObjectWalk()
    • preparePack

      public void preparePack(ProgressMonitor countingMonitor, @NonNull ObjectWalk walk, @NonNull Set<? extends ObjectId> interestingObjects, @NonNull Set<? extends ObjectId> uninterestingObjects, @NonNull Set<? extends ObjectId> noBitmaps) throws IOException
      Prepare the list of objects to be written to the pack stream.

      Basing on these 2 sets, another set of objects to put in a pack file is created: this set consists of all objects reachable (ancestors) from interesting objects, except uninteresting objects and their ancestors. This method uses class ObjectWalk extensively to find out that appropriate set of output objects and their optimal order in output pack. Order is consistent with general git in-pack rules: sort by object type, recency, path and delta-base first.

      Parameters:
      countingMonitor - progress during object enumeration.
      walk - ObjectWalk to perform enumeration.
      interestingObjects - collection of objects to be marked as interesting (start points of graph traversal). Must not be null.
      uninterestingObjects - collection of objects to be marked as uninteresting (end points of graph traversal). Pass NONE if all objects reachable from want are desired, such as when serving a clone.
      noBitmaps - collection of objects to be excluded from bitmap commit selection.
      Throws:
      IOException - when some I/O problem occur during reading objects.
    • willInclude

      public boolean willInclude(AnyObjectId id) throws IOException
      Determine if the pack file will contain the requested object.
      Parameters:
      id - the object to test the existence of.
      Returns:
      true if the object will appear in the output pack file.
      Throws:
      IOException - a cached pack cannot be examined.
    • get

      public ObjectToPack get(AnyObjectId id)
      Lookup the ObjectToPack object for a given ObjectId.
      Parameters:
      id - the object to find in the pack.
      Returns:
      the object we are packing, or null.
    • computeName

      public ObjectId computeName()
      Computes SHA-1 of lexicographically sorted objects ids written in this pack, as used to name a pack file in repository.
      Returns:
      ObjectId representing SHA-1 name of a pack that was created.
    • getIndexVersion

      public int getIndexVersion()
      Returns the index format version that will be written.

      This method can only be invoked after writePack(ProgressMonitor, ProgressMonitor, OutputStream) has been invoked and completed successfully.

      Returns:
      the index format version.
    • writeIndex

      public void writeIndex(OutputStream indexStream) throws IOException
      Create an index file to match the pack file just written.

      Called after writePack(ProgressMonitor, ProgressMonitor, OutputStream).

      Writing an index is only required for local pack storage. Packs sent on the network do not need to create an index.

      Parameters:
      indexStream - output for the index data. Caller is responsible for closing this stream.
      Throws:
      IOException - the index data could not be written to the supplied stream.
    • writeBitmapIndex

      public void writeBitmapIndex(OutputStream bitmapIndexStream) throws IOException
      Create a bitmap index file to match the pack file just written.

      Called after prepareBitmapIndex(ProgressMonitor).

      Parameters:
      bitmapIndexStream - output for the bitmap index data. Caller is responsible for closing this stream.
      Throws:
      IOException - the index data could not be written to the supplied stream.
    • sortByName

      private List<ObjectToPack> sortByName()
    • beginPhase

      private void beginPhase(PackWriter.PackingPhase phase, ProgressMonitor monitor, long cnt)
    • endPhase

      private void endPhase(ProgressMonitor monitor)
    • writePack

      public void writePack(ProgressMonitor compressMonitor, ProgressMonitor writeMonitor, OutputStream packStream) throws IOException
      Write the prepared pack to the supplied stream.

      Called after preparePack(ProgressMonitor, ObjectWalk, Set, Set, Set) or preparePack(ProgressMonitor, Set, Set).

      Performs delta search if enabled and writes the pack stream.

      All reused objects data checksum (Adler32/CRC32) is computed and validated against existing checksum.

      Parameters:
      compressMonitor - progress monitor to report object compression work.
      writeMonitor - progress monitor to report the number of objects written.
      packStream - output stream of pack data. The stream should be buffered by the caller. The caller is responsible for closing the stream.
      Throws:
      IOException - an error occurred reading a local object's data to include in the pack, or writing compressed object data to the output stream.
      WriteAbortedException - the write operation is aborted by ObjectCountCallback .
    • getStatistics

      public PackStatistics getStatistics()
      Get statistics of what this PackWriter did in order to create the final pack stream.
      Returns:
      description of what this PackWriter did in order to create the final pack stream. This should only be invoked after the calls to create the pack/index/bitmap have completed.
    • getState

      public PackWriter.State getState()
      Get snapshot of the current state of this PackWriter.
      Returns:
      snapshot of the current state of this PackWriter.
    • close

      public void close()

      Release all resources used by this writer.

      Specified by:
      close in interface AutoCloseable
    • searchForReuse

      private void searchForReuse(ProgressMonitor monitor) throws IOException
      Throws:
      IOException
    • searchForReuse

      private void searchForReuse(ProgressMonitor monitor, List<ObjectToPack> list) throws IOException, MissingObjectException
      Throws:
      IOException
      MissingObjectException
    • cutDeltaChains

      private void cutDeltaChains(BlockList<ObjectToPack> list) throws IOException
      Throws:
      IOException
    • searchForDeltas

      private void searchForDeltas(ProgressMonitor monitor) throws MissingObjectException, IncorrectObjectTypeException, IOException
      Throws:
      MissingObjectException
      IncorrectObjectTypeException
      IOException
    • findObjectsNeedingDelta

      private int findObjectsNeedingDelta(ObjectToPack[] list, int cnt, int type)
    • reselectNonDelta

      private void reselectNonDelta(ObjectToPack otp) throws IOException
      Throws:
      IOException
    • searchForDeltas

      private void searchForDeltas(ProgressMonitor monitor, ObjectToPack[] list, int cnt) throws MissingObjectException, IncorrectObjectTypeException, LargeObjectException, IOException
      Throws:
      MissingObjectException
      IncorrectObjectTypeException
      LargeObjectException
      IOException
    • singleThreadDeltaSearch

      private void singleThreadDeltaSearch(ProgressMonitor monitor, ObjectToPack[] list, int cnt) throws IOException
      Throws:
      IOException
    • parallelDeltaSearch

      private void parallelDeltaSearch(ProgressMonitor monitor, ObjectToPack[] list, int cnt, int threads) throws IOException
      Throws:
      IOException
    • runTasks

      private static void runTasks(ExecutorService pool, ThreadSafeProgressMonitor pm, DeltaTask.Block tb, List<Throwable> errors) throws IOException
      Throws:
      IOException
    • writeObjects

      private void writeObjects(PackOutputStream out) throws IOException
      Throws:
      IOException
    • writeObjects

      private void writeObjects(PackOutputStream out, List<ObjectToPack> list) throws IOException
      Throws:
      IOException
    • writeObject

      void writeObject(PackOutputStream out, ObjectToPack otp) throws IOException
      Throws:
      IOException
    • writeObjectImpl

      private void writeObjectImpl(PackOutputStream out, ObjectToPack otp) throws IOException
      Throws:
      IOException
    • writeBase

      private void writeBase(PackOutputStream out, ObjectToPack base) throws IOException
      Throws:
      IOException
    • writeWholeObjectDeflate

      private void writeWholeObjectDeflate(PackOutputStream out, ObjectToPack otp) throws IOException
      Throws:
      IOException
    • writeDeltaObjectDeflate

      private void writeDeltaObjectDeflate(PackOutputStream out, ObjectToPack otp) throws IOException
      Throws:
      IOException
    • delta

      private TemporaryBuffer.Heap delta(ObjectToPack otp) throws IOException
      Throws:
      IOException
    • buffer

      private byte[] buffer(AnyObjectId objId) throws IOException
      Throws:
      IOException
    • buffer

      static byte[] buffer(PackConfig config, ObjectReader or, AnyObjectId objId) throws IOException
      Throws:
      IOException
    • deflater

      private Deflater deflater()
    • writeChecksum

      private void writeChecksum(PackOutputStream out) throws IOException
      Throws:
      IOException
    • findObjectsToPack

      private void findObjectsToPack(@NonNull ProgressMonitor countingMonitor, @NonNull ObjectWalk walker, @NonNull Set<? extends ObjectId> want, @NonNull Set<? extends ObjectId> have, @NonNull Set<? extends ObjectId> noBitmaps) throws IOException
      Throws:
      IOException
    • findObjectsToPackUsingBitmaps

      private void findObjectsToPackUsingBitmaps(BitmapWalker bitmapWalker, Set<? extends ObjectId> want, Set<? extends ObjectId> have) throws MissingObjectException, IncorrectObjectTypeException, IOException
      Throws:
      MissingObjectException
      IncorrectObjectTypeException
      IOException
    • pruneEdgesFromObjectList

      private static void pruneEdgesFromObjectList(List<ObjectToPack> list)
    • addObject

      public void addObject(RevObject object) throws IncorrectObjectTypeException
      Include one object to the output file.

      Objects are written in the order they are added. If the same object is added twice, it may be written twice, creating a larger than necessary file.

      Parameters:
      object - the object to add.
      Throws:
      IncorrectObjectTypeException - the object is an unsupported type.
    • addObject

      private void addObject(RevObject object, int pathHashCode)
    • addObject

      private void addObject(AnyObjectId src, int type, int pathHashCode)
    • depthSkip

      private boolean depthSkip(@NonNull RevObject obj, ObjectWalk walker)
      Determines if the object should be omitted from the pack as a result of its depth (probably because of the tree: filter).

      Causes walker to skip traversing the current tree, which ought to have just started traversal, assuming this method is called as soon as a new depth is reached.

      This method increments the treesTraversed statistic.

      Parameters:
      obj - the object to check whether it should be omitted.
      walker - the walker being used for traveresal.
      Returns:
      whether the given object should be skipped.
    • filterAndAddObject

      private void filterAndAddObject(@NonNull AnyObjectId src, int type, int pathHashCode, @NonNull Set<? extends AnyObjectId> want) throws IOException
      Throws:
      IOException
    • exclude

      private boolean exclude(AnyObjectId objectId)
    • select

      public void select(ObjectToPack otp, StoredObjectRepresentation next)
      Select an object representation for this writer.

      An ObjectReader implementation should invoke this method once for each representation available for an object, to allow the writer to find the most suitable one for the output.

      Parameters:
      otp - the object being packed.
      next - the next available representation from the repository.
    • have

      private final boolean have(ObjectToPack ptr, AnyObjectId objectId)
    • prepareBitmapIndex

      public boolean prepareBitmapIndex(ProgressMonitor pm) throws IOException
      Prepares the bitmaps to be written to the bitmap index file.

      Bitmaps can be used to speed up fetches and clones by storing the entire object graph at selected commits. Writing a bitmap index is an optional feature that not all pack users may require.

      Called after writeIndex(OutputStream).

      To reduce memory internal state is cleared during this method, rendering the PackWriter instance useless for anything further than a call to write out the new bitmaps with writeBitmapIndex(OutputStream).

      Parameters:
      pm - progress monitor to report bitmap building work.
      Returns:
      whether a bitmap index may be written.
      Throws:
      IOException - when some I/O problem occur during reading objects.
    • reuseDeltaFor

      private boolean reuseDeltaFor(ObjectToPack otp)