Package org.apache.jackrabbit.spi

Interface Path

All Superinterfaces:
Serializable
public interface Path extends Serializable
The Path interface defines the SPI level representation of a JCR path. It consists of an ordered list of Path.Element objects and is immutable.

A Path.Element is either named or one of the following special elements:

  • the current element (Notation: "."),
  • the parent element (Notation: ".."),
  • the root element (Notation: {}), which can only occur as the first element in a path, or
  • an identifier element, which can only occur as the first element in a path.

A Path is defined to have the following characteristics:

Equality:
Two paths are equal if they consist of the same elements.

Length:
The length of a path is the number of its elements.

Depth:
The depth of a path is

  • 0 for the root path,
  • 0 for a path consisting of an identifier element only,
  • 0 for the path consisting of the current element only,
  • -1 for the path consisting of the parent element only,
  • 1 for the path consisting of a single named element,
  • depth(P) + depth(Q) for the path P/Q.

The depth of a normalized absolute path equals its length minus 1.

Absolute vs. Relative
A path can be absolute or relative:
A path is absolute if its first element is the root or an identifier element. A path is relative if it is not absolute.

  • An absolute path is valid if its depth is greater or equals 0. A relative path is always valid.
  • Two absolute paths are equivalent if "they refer to the same item in the hierarchy".
  • Two relative paths P and Q are equivalent if for every absolute path R such that R/P and R/Q are valid, R/P and R/Q are equivalent.

Normalization:
A path P is normalized if P has minimal length amongst the set of all paths Q which are equivalent to P.
This means that '.' and '..' elements are resolved as much as possible. An absolute path it is normalized if it is not identifier-based and contains no current or parent elements. The normalization of a path is unique.

Equivalence:
Path P is equivalent to path Q (in the above sense) if the normalization of P is equal to the normalization of Q. This is an equivalence relation (i.e. reflexive, transitive, and symmetric).

Canonical Paths:
A path is canonical if its absolute and normalized.

Hierarchical Relationship:
The ancestor relationship is a strict partial order (i.e. irreflexive, transitive, and asymmetric). Path P is a direct ancestor of path Q if P is equivalent to Q/..
Path P is an ancestor of path Q if

  • P is a direct ancestor of Q or
  • P is a direct ancestor of some path S which is an ancestor of Q.

Path P is an descendant of path Q if

  • Path P is a descendant of path Q if Q is an ancestor of P.

  • Nested Class Summary

    Nested Classes
    Modifier and Type
    Interface
    Description
    static interface 
    Path.Element
    Object representation of a single JCR path element.

  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    static final char
    DELIMITER
    Delimiter used in order to concatenate the Path.Element objects upon getString().
    static final int
    INDEX_DEFAULT
    Constant representing the default (initial) index value.
    static final int
    INDEX_UNDEFINED
    Constant representing an undefined index value
    static final int
    ROOT_DEPTH
    Constant defining the depth of the root path

  • Method Summary

    Modifier and Type
    Method
    Description
    Path
    computeRelativePath(Path other)
    Computes the relative path from this absolute path to other.
    boolean
    denotesCurrent()
    Checks if the last path element is the current element (".").
    boolean
    denotesIdentifier()
    Test if this path consists of a single identifier element.
    boolean
    denotesName()
    Checks if the last path element is a named and optionally indexed element.
    boolean
    denotesParent()
    Checks if the last path element is the parent element ("..").
    boolean
    denotesRoot()
    Tests whether this is the root path, i.e.
    Path
    getAncestor(int degree)
    Normalizes this path and returns the ancestor path of the specified relative degree.
    int
    getAncestorCount()
    Returns the number of ancestors of this path.
    Path
    getCanonicalPath()
    Returns the canonical path representation of this path.
    int
    getDepth()
    Returns the depth of this path.
    Path.Element[]
    getElements()
    Returns the elements of this path.
    Path
    getFirstElements()
    Returns a path that consists of all but the last element of this path.
    String
    getIdentifier()
    Returns the identifier of a single identifier element.
    int
    getIndex()
    Returns the index of the last path element, or INDEX_UNDEFINED if the index is not defined or not applicable.
    Path
    getLastElement()
    Returns a path that consists of only the last element of this path.
    int
    getLength()
    Returns the length of this path, i.e.
    Name
    getName()
    Returns the name of the last path element, or null for an identifier.
    Path.Element
    getNameElement()
    Returns the name element (i.e.
    int
    getNormalizedIndex()
    Returns the normalized index of the last path element.
    Path
    getNormalizedPath()
    Returns the normalized path representation of this path.
    String
    getString()
    Returns the String representation of this Path as it is used by PathFactory.create(String).
    boolean
    isAbsolute()
    Tests whether this path is absolute, i.e.
    boolean
    isAncestorOf(Path other)
    Determines if this path is an ancestor of the specified path, based on their (absolute or relative) hierarchy level as returned by getDepth().
    boolean
    isCanonical()
    Tests whether this path is canonical, i.e.
    boolean
    isDescendantOf(Path other)
    Determines if this path is a descendant of the specified path, based on their (absolute or relative) hierarchy level as returned by getDepth().
    boolean
    isEquivalentTo(Path other)
    Determines if the the other path would be equal to this path if both of them are normalized.
    boolean
    isIdentifierBased()
    Test if this path represents an unresolved identifier-based path.
    boolean
    isNormalized()
    Tests whether this path is normalized, i.e.
    Path
    resolve(Path relative)
    Resolves the given path against this path.
    Path
    resolve(Path.Element element)
    Resolves the given path element against this path.
    Path
    subPath(int from, int to)
    Returns a new Path consisting of those Path.Element objects between the given from, inclusive, and the given to, exclusive.

  • Field Details

    • INDEX_UNDEFINED

      static final int INDEX_UNDEFINED
      Constant representing an undefined index value
      See Also:

    • INDEX_DEFAULT

      static final int INDEX_DEFAULT
      Constant representing the default (initial) index value.
      See Also:

    • ROOT_DEPTH

      static final int ROOT_DEPTH
      Constant defining the depth of the root path
      See Also:

    • DELIMITER

      static final char DELIMITER
      Delimiter used in order to concatenate the Path.Element objects upon getString().
      See Also:

  • Method Details

    • getName

      Name getName()
      Returns the name of the last path element, or null for an identifier. The names of the special root, current and parent elements are "", "." and ".." in the default namespace.
      Returns:
      name of the last path element, or null

    • getIndex

      int getIndex()
      Returns the index of the last path element, or INDEX_UNDEFINED if the index is not defined or not applicable. The index of an identifier or the special root, current or parent element is always undefined.
      Returns:
      index of the last path element, or INDEX_UNDEFINED

    • getNormalizedIndex

      int getNormalizedIndex()
      Returns the normalized index of the last path element. The normalized index of an element with an undefined index is INDEX_DEFAULT.
      Returns:
      normalized index of the last path element

    • getIdentifier

      String getIdentifier()
      Returns the identifier of a single identifier element. Returns null for non-identifier paths or identifier paths with other relative path elements.
      Returns:
      identifier, or null

    • denotesRoot

      boolean denotesRoot()
      Tests whether this is the root path, i.e. "/".
      Returns:
      true if this is the root path, false otherwise.

    • denotesIdentifier

      boolean denotesIdentifier()
      Test if this path consists of a single identifier element.
      Returns:
      true if this path is an identifier

    • denotesParent

      boolean denotesParent()
      Checks if the last path element is the parent element ("..").
      Returns:
      true if the last path element is the parent element, false otherwise

    • denotesCurrent

      boolean denotesCurrent()
      Checks if the last path element is the current element (".").
      Returns:
      true if the last path element is the current element, false otherwise

    • denotesName

      boolean denotesName()
      Checks if the last path element is a named and optionally indexed element.
      Returns:
      true if the last path element is a named element, false otherwise

    • isIdentifierBased

      boolean isIdentifierBased()
      Test if this path represents an unresolved identifier-based path.
      Returns:
      true if this path represents an unresolved identifier-based path.

    • isAbsolute

      boolean isAbsolute()
      Tests whether this path is absolute, i.e. whether it starts with "/" or is an identifier based path.
      Returns:
      true if this path is absolute; false otherwise.

    • isCanonical

      boolean isCanonical()
      Tests whether this path is canonical, i.e. whether it is absolute and does not contain redundant elements such as "." and "..".
      Returns:
      true if this path is canonical; false otherwise.
      See Also:

    • isNormalized

      boolean isNormalized()
      Tests whether this path is normalized, i.e. whether it does not contain redundant elements such as "." and "..".

      Note that a normalized path can still contain ".." elements if they are not redundant, e.g. "../../a/b/c" would be a normalized relative path, whereas "../a/../../a/b/c" wouldn't (although they're semantically equivalent).

      Returns:
      true if this path is normalized; false otherwise.
      See Also:

    • getNormalizedPath

      Path getNormalizedPath() throws RepositoryException
      Returns the normalized path representation of this path.

      If the path cannot be normalized (e.g. if an absolute path is normalized that would result in a 'negative' path) a RepositoryException is thrown.

      Returns:
      a normalized path representation of this path.
      Throws:
      RepositoryException - if the path cannot be normalized.
      See Also:

    • getCanonicalPath

      Path getCanonicalPath() throws RepositoryException
      Returns the canonical path representation of this path.

      If the path is relative or cannot be normalized a RepositoryException is thrown.

      Returns:
      a canonical path representation of this path.
      Throws:
      RepositoryException - if this path can not be canonicalized (e.g. if it is relative).

    • resolve

      Path resolve(Path.Element element)
      Resolves the given path element against this path. If the given element is absolute (i.e. the root or an identifier element), then a path containing just that element is returned. Otherwise the returned path consists of this path followed by the given element.
      Parameters:
      element - path element
      Returns:
      resolved path

    • resolve

      Path resolve(Path relative)
      Resolves the given path against this path. If the given path is absolute, then it is returned as-is. Otherwise the path is resolved relative to this path and the resulting resolved path is returned.
      Parameters:
      relative - the path to be resolved
      Returns:
      resolved path

    • computeRelativePath

      Path computeRelativePath(Path other) throws RepositoryException
      Computes the relative path from this absolute path to other.
      Parameters:
      other - an absolute path.
      Returns:
      the relative path from this path to other path.
      Throws:
      RepositoryException - if either this or other path is not absolute.

    • getAncestor

      Path getAncestor(int degree) throws IllegalArgumentException, PathNotFoundException, RepositoryException
      Normalizes this path and returns the ancestor path of the specified relative degree.

      An ancestor of relative degree x is the path that is x levels up along the path.

      • degree = 0 returns this path.
      • degree = 1 returns the parent of this path.
      • degree = 2 returns the grandparent of this path.
      • And so on to degree = n, where n is the depth of this path, which returns the root path.

      If this path is relative the implementation may not be able to determine if the ancestor at degree exists. Such an implementation should properly build the ancestor (i.e. parent of .. is ../..) and leave if it the caller to throw PathNotFoundException.

      Parameters:
      degree - the relative degree of the requested ancestor.
      Returns:
      the normalized ancestor path of the specified degree.
      Throws:
      IllegalArgumentException - if degree is negative.
      PathNotFoundException - if the implementation is able to determine that there is no ancestor of the specified degree. In case of this being an absolute path, this would be the case if degree is greater that the depth of this path.
      RepositoryException - If the implementation is not able to determine the ancestor of the specified degree for some other reason.

    • getAncestorCount

      int getAncestorCount()
      Returns the number of ancestors of this path. This is the equivalent of getDepth() in case of a absolute path. For relative path the number of ancestors cannot be determined and -1 should be returned.
      Returns:
      the number of ancestors of this path or -1 if the number of ancestors cannot be determined.
      See Also:

    • getLength

      int getLength()
      Returns the length of this path, i.e. the number of its elements. Note that the root element "/" counts as a separate element, e.g. the length of "/a/b/c" is 4 whereas the length of "a/b/c" is 3.

      Also note that the special elements "." and ".." are not treated specially, e.g. both "/a/./.." and "/a/b/c" have a length of 4 but this value does not necessarily reflect the true hierarchy level as returned by getDepth().

      Returns:
      the length of this path
      See Also:

    • getDepth

      int getDepth()
      Returns the depth of this path. The depth reflects the absolute or relative hierarchy level this path is representing, depending on whether this path is an absolute or a relative path. The depth also takes '.' and '..' elements into account. The depth of the root path, an identifier and the current path must be 0.

      Note that the returned value might be negative if this path is not canonical, e.g. the depth of "../../a" is -1.

      Returns:
      the depth this path
      See Also:

    • isEquivalentTo

      boolean isEquivalentTo(Path other) throws IllegalArgumentException, RepositoryException
      Determines if the the other path would be equal to this path if both of them are normalized.
      Parameters:
      other - Another path.
      Returns:
      true if the given other path is equivalent to this path.
      Throws:
      IllegalArgumentException - if the given path is null or if not both paths are either absolute or relative.
      RepositoryException - if any of the path cannot be normalized.

    • isAncestorOf

      boolean isAncestorOf(Path other) throws IllegalArgumentException, RepositoryException
      Determines if this path is an ancestor of the specified path, based on their (absolute or relative) hierarchy level as returned by getDepth(). In case of undefined ancestor/descendant relationship that might occur with relative paths, the return value should be false.
      Returns:
      true if other is a descendant; otherwise false.
      Throws:
      IllegalArgumentException - if the given path is null or if not both paths are either absolute or relative.
      RepositoryException - if any of the path cannot be normalized.
      See Also:

    • isDescendantOf

      boolean isDescendantOf(Path other) throws IllegalArgumentException, RepositoryException
      Determines if this path is a descendant of the specified path, based on their (absolute or relative) hierarchy level as returned by getDepth(). In case of undefined ancestor/descendant relationship that might occur with relative paths, the return value should be false.
      Returns:
      true if other is an ancestor; otherwise false.
      Throws:
      IllegalArgumentException - if the given path is null or if not both paths are either absolute or relative.
      RepositoryException - if any of the path cannot be normalized.
      See Also:

    • subPath

      Path subPath(int from, int to) throws IllegalArgumentException
      Returns a new Path consisting of those Path.Element objects between the given from, inclusive, and the given to, exclusive. An IllegalArgumentException is thrown if from is greater or equal than to or if any of both params is out of the possible range.
      Parameters:
      from - index of the element to start with and low endpoint (inclusive) within the list of elements to use for the sub-path.
      to - index of the element outside of the range i.e. high endpoint (exclusive) within the list of elements to use for the sub-path.
      Returns:
      a new Path consisting of those Path.Element objects between the given from, inclusive, and the given to, exclusive.
      Throws:
      IllegalArgumentException - if from is greater or equal than to or if any of both params is out of the possible range.

    • getElements

      Path.Element[] getElements()
      Returns the elements of this path.
      Returns:
      the elements of this path.

    • getNameElement

      Path.Element getNameElement()
      Returns the name element (i.e. the last element) of this path.
      Returns:
      the name element of this path

    • getLastElement

      Path getLastElement()
      Returns a path that consists of only the last element of this path.
      Returns:
      last element of this path
      See Also:

    • getFirstElements

      Path getFirstElements()
      Returns a path that consists of all but the last element of this path. Returns null if this path contains just a single element.
      Returns:
      first elements of this path, or null
      See Also:

    • getString

      String getString()
      Returns the String representation of this Path as it is used by PathFactory.create(String).

      The String representation must consist of the String representation of its elements separated by DELIMITER.

      Returns:
      Returns the String representation of this Path.
      See Also: