Package net.sf.saxon.om

Class AxisInfo

java.lang.Object
net.sf.saxon.om.AxisInfo
public final class AxisInfo extends Object
An axis, that is a direction of navigation in the document structure.

  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    static final int
    ANCESTOR
    Constant representing the ancestor axis
    static final int
    ANCESTOR_OR_SELF
    Constant representing the ancestor-or-self axis
    static final int
    ATTRIBUTE
    Constant representing the attribute axis
    static final String[]
    axisName
    Table giving the name of each axis as used in XPath, for example "ancestor-or-self"
    static final int
    CHILD
    Constant representing the child axis
    static final int
    DESCENDANT
    Constant representing the descendant axis
    static final int
    DESCENDANT_OR_SELF
    Constant representing the descendant-or-self axis
    static int[]
    excludeSelfAxis
    Give the corresponding axis if the self node is excluded.
    static final int
    FOLLOWING
    Constant representing the following axis
    static final int
    FOLLOWING_SIBLING
    Constant representing the following-sibling axis
    static int[]
    inverseAxis
    For each axis, determine the inverse axis, in the sense that if A is on axis X starting at B, the B is on the axis inverseAxis[X] starting at A.
    static final boolean[]
    isForwards
    Table indicating for each axis whether it is in forwards document order
    static final boolean[]
    isPeerAxis
    Table indicating for each axis whether it is a peer axis.
    static final boolean[]
    isSubtreeAxis
    Table indicating for each axis whether it is contained within the subtree rooted at the origin node.
    static final int
    NAMESPACE
    Constant representing the namespace axis
    static final int
    PARENT
    Constant representing the parent axis
    static final int
    PRECEDING
    Constant representing the preceding axis
    static final int
    PRECEDING_OR_ANCESTOR
    Constant representing the preceding-or-ancestor axis.
    static final int
    PRECEDING_SIBLING
    Constant representing the preceding-sibling axis
    static final short[]
    principalNodeType
    Table indicating the principal node type of each axis
    static final UType[]
    principalNodeUType
     
    static final int
    SELF
    Constant representing the self axis

  • Method Summary

    Modifier and Type
    Method
    Description
    static boolean
    containsNodeKind(int axis, int nodeKind)
    Determine whether a given kind of node can be found on a given axis.
    static int
    getAxisNumber(String name)
    Resolve an axis name into a symbolic constant representing the axis
    static UType
    getTargetUType(UType origin, int axis)
    Given a context item type and an axis, determine the kinds of nodes that can be returned
    static boolean
    isAlwaysEmpty(int axis, int nodeKind)
    Ask whether a given axis can contain any nodes when starting at the specified node kind.

    Methods inherited from class java.lang.Object

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

  • Field Details

    • ANCESTOR

      public static final int ANCESTOR
      Constant representing the ancestor axis
      See Also:

    • ANCESTOR_OR_SELF

      public static final int ANCESTOR_OR_SELF
      Constant representing the ancestor-or-self axis
      See Also:

    • ATTRIBUTE

      public static final int ATTRIBUTE
      Constant representing the attribute axis
      See Also:

    • CHILD

      public static final int CHILD
      Constant representing the child axis
      See Also:

    • DESCENDANT

      public static final int DESCENDANT
      Constant representing the descendant axis
      See Also:

    • DESCENDANT_OR_SELF

      public static final int DESCENDANT_OR_SELF
      Constant representing the descendant-or-self axis
      See Also:

    • FOLLOWING

      public static final int FOLLOWING
      Constant representing the following axis
      See Also:

    • FOLLOWING_SIBLING

      public static final int FOLLOWING_SIBLING
      Constant representing the following-sibling axis
      See Also:

    • NAMESPACE

      public static final int NAMESPACE
      Constant representing the namespace axis
      See Also:

    • PARENT

      public static final int PARENT
      Constant representing the parent axis
      See Also:

    • PRECEDING

      public static final int PRECEDING
      Constant representing the preceding axis
      See Also:

    • PRECEDING_SIBLING

      public static final int PRECEDING_SIBLING
      Constant representing the preceding-sibling axis
      See Also:

    • SELF

      public static final int SELF
      Constant representing the self axis
      See Also:

    • PRECEDING_OR_ANCESTOR

      public static final int PRECEDING_OR_ANCESTOR
      Constant representing the preceding-or-ancestor axis. This axis is used internally by the xsl:number implementation, it returns the union of the preceding axis and the ancestor axis.
      See Also:

    • principalNodeType

      public static final short[] principalNodeType
      Table indicating the principal node type of each axis

    • principalNodeUType

      public static final UType[] principalNodeUType

    • isForwards

      public static final boolean[] isForwards
      Table indicating for each axis whether it is in forwards document order

    • isPeerAxis

      public static final boolean[] isPeerAxis
      Table indicating for each axis whether it is a peer axis. An axis is a peer axis if no node on the axis is an ancestor of another node on the axis.

    • isSubtreeAxis

      public static final boolean[] isSubtreeAxis
      Table indicating for each axis whether it is contained within the subtree rooted at the origin node.

    • axisName

      public static final String[] axisName
      Table giving the name of each axis as used in XPath, for example "ancestor-or-self"

    • inverseAxis

      public static int[] inverseAxis
      For each axis, determine the inverse axis, in the sense that if A is on axis X starting at B, the B is on the axis inverseAxis[X] starting at A. This doesn't quite work for the PARENT axis, which has no simple inverse: this table gives the inverse as CHILD

    • excludeSelfAxis

      public static int[] excludeSelfAxis
      Give the corresponding axis if the self node is excluded. (Doesn't really work for the self axis itself).

  • Method Details

    • getAxisNumber

      public static int getAxisNumber(String name) throws XPathException
      Resolve an axis name into a symbolic constant representing the axis
      Parameters:
      name - the name of the axis
      Returns:
      integer value representing the named axis
      Throws:
      XPathException - if the axis name is not one of the defined axes

    • isAlwaysEmpty

      public static boolean isAlwaysEmpty(int axis, int nodeKind)
      Ask whether a given axis can contain any nodes when starting at the specified node kind. For example, the attribute axis when starting at an attribute node will always be empty
      Parameters:
      axis - the axis, for example ATTRIBUTE
      nodeKind - the node kind of the origin node, for example Type.ATTRIBUTE
      Returns:
      true if no nodes will ever appear on the specified axis when starting at the specified node kind.

    • containsNodeKind

      public static boolean containsNodeKind(int axis, int nodeKind)
      Determine whether a given kind of node can be found on a given axis. For example, the attribute axis will never contain any element nodes.
      Parameters:
      axis - the axis, for example ATTRIBUTE
      nodeKind - the node kind of the origin node, for example Type.ELEMENT
      Returns:
      true if the given kind of node can appear on the specified axis

    • getTargetUType

      public static UType getTargetUType(UType origin, int axis)
      Given a context item type and an axis, determine the kinds of nodes that can be returned
      Parameters:
      origin - the context item type, as a UType representing one or more node kinds
      axis - identifies the axis
      Returns:
      the set of possible node kinds in the result of the axis expression, as a UType