Class DirCacheTree


  • public class DirCacheTree
    extends java.lang.Object
    Single tree record from the 'TREE' DirCache extension.

    A valid cache tree record contains the object id of a tree object and the total number of DirCacheEntry instances (counted recursively) from the DirCache contained within the tree. This information facilitates faster traversal of the index and quicker generation of tree objects prior to creating a new commit.

    An invalid cache tree record indicates a known subtree whose file entries have changed in ways that cause the tree to no longer have a known object id. Invalid cache tree records must be revalidated prior to use.

    • Field Detail

      • NO_NAME

        private static final byte[] NO_NAME
      • NO_CHILDREN

        private static final DirCacheTree[] NO_CHILDREN
      • TREE_CMP

        private static final java.util.Comparator<DirCacheTree> TREE_CMP
      • parent

        private DirCacheTree parent
        Tree this tree resides in; null if we are the root.
      • encodedName

        byte[] encodedName
        Name of this tree within its parent.
      • entrySpan

        private int entrySpan
        Number of DirCacheEntry records that belong to this tree.
      • id

        private ObjectId id
        Unique SHA-1 of this tree; null if invalid.
      • childCnt

        private int childCnt
        Number of valid children in children.
    • Constructor Detail

      • DirCacheTree

        DirCacheTree()
      • DirCacheTree

        private DirCacheTree​(DirCacheTree myParent,
                             byte[] path,
                             int pathOff,
                             int pathLen)
    • Method Detail

      • write

        void write​(byte[] tmp,
                   java.io.OutputStream os)
            throws java.io.IOException
        Throws:
        java.io.IOException
      • isValid

        public boolean isValid()
        Determine if this cache is currently valid.

        A valid cache tree knows how many DirCacheEntry instances from the parent DirCache reside within this tree (recursively enumerated). It also knows the object id of the tree, as the tree should be readily available from the repository's object database.

        Returns:
        true if this tree is knows key details about itself; false if the tree needs to be regenerated.
      • getEntrySpan

        public int getEntrySpan()
        Get the number of entries this tree spans within the DirCache.

        If this tree is not valid (see isValid()) this method's return value is always strictly negative (less than 0) but is otherwise an undefined result.

        Returns:
        total number of entries (recursively) contained within this tree.
      • getChildCount

        public int getChildCount()
        Get the number of cached subtrees contained within this tree.
        Returns:
        number of child trees available through this tree.
      • getChild

        public DirCacheTree getChild​(int i)
        Get the i-th child cache tree.
        Parameters:
        i - index of the child to obtain.
        Returns:
        the child tree.
      • getObjectId

        public ObjectId getObjectId()
        Get the tree's ObjectId.

        If isValid() returns false this method will return null.

        Returns:
        ObjectId of this tree or null.
        Since:
        4.3
      • getNameString

        public java.lang.String getNameString()
        Get the tree's name within its parent.

        This method is not very efficient and is primarily meant for debugging and final output generation. Applications should try to avoid calling it, and if invoked do so only once per interesting entry, where the name is absolutely required for correct function.

        Returns:
        name of the tree. This does not contain any '/' characters.
      • getPathString

        public java.lang.String getPathString()
        Get the tree's path within the repository.

        This method is not very efficient and is primarily meant for debugging and final output generation. Applications should try to avoid calling it, and if invoked do so only once per interesting entry, where the name is absolutely required for correct function.

        Returns:
        path of the tree, relative to the repository root. If this is not the root tree the path ends with '/'. The root tree's path string is the empty string ("").
      • writeTree

        ObjectId writeTree​(DirCacheEntry[] cache,
                           int cIdx,
                           int pathOffset,
                           ObjectInserter ow)
                    throws UnmergedPathException,
                           java.io.IOException
        Write (if necessary) this tree to the object store.
        Parameters:
        cache - the complete cache from DirCache.
        cIdx - first position of cache that is a member of this tree. The path of cache[cacheIdx].path for the range [0,pathOff-1) matches the complete path of this tree, from the root of the repository.
        pathOffset - number of bytes of cache[cacheIdx].path that matches this tree's path. The value at array position cache[cacheIdx].path[pathOff-1] is always '/' if pathOff is > 0.
        ow - the writer to use when serializing to the store.
        Returns:
        identity of this tree.
        Throws:
        UnmergedPathException - one or more paths contain higher-order stages (stage > 0), which cannot be stored in a tree object.
        java.io.IOException - an unexpected error occurred writing to the object store.
      • appendName

        private void appendName​(java.lang.StringBuilder r)
      • nameLength

        final int nameLength()
      • contains

        final boolean contains​(byte[] a,
                               int aOff,
                               int aLen)
      • validate

        void validate​(DirCacheEntry[] cache,
                      int cCnt,
                      int cIdx,
                      int pathOff)
        Update (if necessary) this tree's entrySpan.
        Parameters:
        cache - the complete cache from DirCache.
        cCnt - number of entries in cache that are valid for iteration.
        cIdx - first position of cache that is a member of this tree. The path of cache[cacheIdx].path for the range [0,pathOff-1) matches the complete path of this tree, from the root of the repository.
        pathOff - number of bytes of cache[cacheIdx].path that matches this tree's path. The value at array position cache[cacheIdx].path[pathOff-1] is always '/' if pathOff is > 0.
      • insertChild

        private void insertChild​(int stIdx,
                                 DirCacheTree st)
      • removeChild

        private void removeChild​(int stIdx)
      • peq

        static boolean peq​(byte[] a,
                           byte[] b,
                           int aLen)
      • namecmp

        private static int namecmp​(byte[] a,
                                   int aPos,
                                   DirCacheTree ct)
      • slash

        private static int slash​(byte[] a,
                                 int aPos)
      • toString

        public java.lang.String toString()
        Overrides:
        toString in class java.lang.Object