Class ObjectToPack

  • All Implemented Interfaces:
    java.io.Serializable, java.lang.Comparable<AnyObjectId>
    Direct Known Subclasses:
    DfsObjectToPack, LocalObjectToPack

    public class ObjectToPack
    extends PackedObjectInfo
    Per-object state used by PackWriter.

    PackWriter uses this class to track the things it needs to include in the newly generated pack file, and how to efficiently obtain the raw data for each object as they are written to the output stream.

    See Also:
    Serialized Form
    • Field Detail

      • deltaBase

        private ObjectId deltaBase
        Other object being packed that this will delta against.
      • flags

        private int flags
        Bit field, from bit 0 to bit 31:
        • 1 bit: canReuseAsIs
        • 1 bit: deltaAttempted
        • 1 bit: doNotDelta
        • 1 bit: edgeObject
        • 1 bit: unused
        • 3 bits: type
        • 4 bits: subclass flags (if any)
        • --
        • 20 bits: deltaDepth
      • pathHash

        private int pathHash
        Hash of the object's tree path.
      • cachedDelta

        private DeltaCache.Ref cachedDelta
        If present, deflated delta instruction stream for this object.
    • Constructor Detail

      • ObjectToPack

        public ObjectToPack​(AnyObjectId src,
                            int type)
        Construct for the specified object id.
        Parameters:
        src - object id of object for packing
        type - real type code of the object, not its in-pack type.
    • Method Detail

      • getDeltaBaseId

        public final ObjectId getDeltaBaseId()
        Get delta base object id if object is going to be packed in delta representation
        Returns:
        delta base object id if object is going to be packed in delta representation; null otherwise - if going to be packed as a whole object.
      • getDeltaBase

        public final ObjectToPack getDeltaBase()
        Get delta base object to pack if object is going to be packed in delta representation and delta is specified as object to pack
        Returns:
        delta base object to pack if object is going to be packed in delta representation and delta is specified as object to pack; null otherwise - if going to be packed as a whole object or delta base is specified only as id.
      • setDeltaBase

        final void setDeltaBase​(ObjectId deltaBase)
        Set delta base for the object. Delta base set by this method is used by PackWriter to write object - determines its representation in a created pack.
        Parameters:
        deltaBase - delta base object or null if object should be packed as a whole object.
      • clearDeltaBase

        final void clearDeltaBase()
      • isDeltaRepresentation

        public final boolean isDeltaRepresentation()
        Whether object is going to be written as delta
        Returns:
        true if object is going to be written as delta; false otherwise.
      • isWritten

        public final boolean isWritten()
        Check if object is already written in a pack. This information is used to achieve delta-base precedence in a pack file.
        Returns:
        true if object is already written; false otherwise.
      • getType

        public final int getType()
        Get the object type.
        Overrides:
        getType in class PackedObjectInfo
        Returns:
        the object type. The default type is OBJ_BAD, which is considered as unknown or invalid type.
      • getDeltaDepth

        final int getDeltaDepth()
      • setDeltaDepth

        final void setDeltaDepth​(int d)
      • getChainLength

        final int getChainLength()
      • setChainLength

        final void setChainLength​(int len)
      • clearChainLength

        final void clearChainLength()
      • wantWrite

        final boolean wantWrite()
      • markWantWrite

        final void markWantWrite()
      • isReuseAsIs

        public final boolean isReuseAsIs()
        Whether an existing representation was selected to be reused as-is into the pack stream.
        Returns:
        true if an existing representation was selected to be reused as-is into the pack stream.
      • setReuseAsIs

        final void setReuseAsIs()
      • clearReuseAsIs

        protected void clearReuseAsIs()
        Forget the reuse information previously stored.

        Implementations may subclass this method, but they must also invoke the super version with super.clearReuseAsIs() to ensure the flag is properly cleared for the writer.

      • isDoNotDelta

        final boolean isDoNotDelta()
      • setDoNotDelta

        final void setDoNotDelta()
      • isEdge

        final boolean isEdge()
      • setEdge

        final void setEdge()
      • doNotAttemptDelta

        final boolean doNotAttemptDelta()
      • setDeltaAttempted

        final void setDeltaAttempted​(boolean deltaAttempted)
      • getExtendedFlags

        protected final int getExtendedFlags()
        Get the extended flags on this object, in the range [0x0, 0xf].
        Returns:
        the extended flags on this object, in the range [0x0, 0xf].
      • isExtendedFlag

        protected final boolean isExtendedFlag​(int flag)
        Determine if a particular extended flag bit has been set. This implementation may be faster than calling getExtendedFlags() and testing the result.
        Parameters:
        flag - the flag mask to test, must be between 0x0 and 0xf.
        Returns:
        true if any of the bits matching the mask are non-zero.
      • setExtendedFlag

        protected final void setExtendedFlag​(int flag)
        Set an extended flag bit. This implementation is more efficient than getting the extended flags, adding the bit, and setting them all back.
        Parameters:
        flag - the bits to set, must be between 0x0 and 0xf.
      • clearExtendedFlag

        protected final void clearExtendedFlag​(int flag)
        Clear an extended flag bit. This implementation is more efficient than getting the extended flags, removing the bit, and setting them all back.
        Parameters:
        flag - the bits to clear, must be between 0x0 and 0xf.
      • setExtendedFlags

        protected final void setExtendedFlags​(int extFlags)
        Set the extended flags used by the subclass. Subclass implementations may store up to 4 bits of information inside of the internal flags field already used by the base ObjectToPack instance.
        Parameters:
        extFlags - additional flag bits to store in the flags field. Due to space constraints only values [0x0, 0xf] are permitted.
      • getFormat

        final int getFormat()
      • getWeight

        final int getWeight()
      • setWeight

        final void setWeight​(int weight)
      • getPathHash

        final int getPathHash()
      • setPathHash

        final void setPathHash​(int hc)
      • getCachedSize

        final int getCachedSize()
      • setCachedSize

        final void setCachedSize​(int sz)
      • select

        public void select​(StoredObjectRepresentation ref)
        Remember a specific representation for reuse at a later time.

        Implementers should remember the representation chosen, so it can be reused at a later time. PackWriter may invoke this method multiple times for the same object, each time saving the current best representation found.

        Parameters:
        ref - the object representation.