Package org.apache.xpath.axes

Class PredicatedNodeTest

java.lang.Object
org.apache.xpath.Expression
org.apache.xpath.patterns.NodeTest
org.apache.xpath.axes.PredicatedNodeTest
All Implemented Interfaces:
Serializable, SourceLocator, SubContextList, ExpressionNode, XPathVisitable
Direct Known Subclasses:
AxesWalker, LocPathIterator
public abstract class PredicatedNodeTest
extends NodeTest
implements SubContextList
See Also:
Serialized Form

  • Field Details

    • m_predCount

      protected int m_predCount

    • m_foundLast

      protected transient boolean m_foundLast
      This is true if nextNode returns null.

    • m_lpi

      protected LocPathIterator m_lpi
      The owning location path iterator.

    • m_proximityPositions

      protected transient int[] m_proximityPositions
      An array of counts that correspond to the number of predicates the step contains.

  • Method Details

    • clone

      public Object clone() throws CloneNotSupportedException
      Get a cloned PrdicatedNodeTest.
      Overrides:
      clone in class Object
      Returns:
      A new PredicatedNodeTest that can be used without mutating this one.
      Throws:
      CloneNotSupportedException

    • getPredicateCount

      public int getPredicateCount()
      Get the number of predicates that this walker has.
      Returns:
      the number of predicates that this walker has.

    • setPredicateCount

      public void setPredicateCount​(int count)
      Set the number of predicates that this walker has. This does more that one would think, as it creates a new predicate array of the size of the count argument, and copies count predicates into the new one from the old, and then reassigns the predicates value. All this to keep from having to have a predicate count value.
      Parameters:
      count - The number of predicates, which must be equal or less than the existing count.

    • initPredicateInfo

      protected void initPredicateInfo​(Compiler compiler, int opPos) throws TransformerException
      Init predicate info.
      Parameters:
      compiler - The Compiler object that has information about this walker in the op map.
      opPos - The op code position of this location step.
      Throws:
      TransformerException

    • getPredicate

      public Expression getPredicate​(int index)
      Get a predicate expression at the given index.
      Parameters:
      index - Index of the predicate.
      Returns:
      A predicate expression.

    • getProximityPosition

      public int getProximityPosition()
      Get the current sub-context position.
      Returns:
      The node position of this walker in the sub-context node list.

    • getProximityPosition

      public int getProximityPosition​(XPathContext xctxt)
      Get the current sub-context position.
      Specified by:
      getProximityPosition in interface SubContextList
      Parameters:
      xctxt - The XPath runtime context.
      Returns:
      The node position of this walker in the sub-context node list.

    • getLastPos

      public abstract int getLastPos​(XPathContext xctxt)
      Get the index of the last node that can be itterated to.
      Specified by:
      getLastPos in interface SubContextList
      Parameters:
      xctxt - XPath runtime context.
      Returns:
      the index of the last node that can be itterated to.

    • getProximityPosition

      protected int getProximityPosition​(int predicateIndex)
      Get the current sub-context position.
      Parameters:
      predicateIndex - The index of the predicate where the proximity should be taken from.
      Returns:
      The node position of this walker in the sub-context node list.

    • resetProximityPositions

      public void resetProximityPositions()
      Reset the proximity positions counts.

    • initProximityPosition

      public void initProximityPosition​(int i) throws TransformerException
      Init the proximity position to zero for a forward axes.
      Parameters:
      i - The index into the m_proximityPositions array.
      Throws:
      TransformerException

    • countProximityPosition

      protected void countProximityPosition​(int i)
      Count forward one proximity position.
      Parameters:
      i - The index into the m_proximityPositions array, where the increment will occur.

    • isReverseAxes

      public boolean isReverseAxes()
      Tells if this is a reverse axes.
      Returns:
      false, unless a derived class overrides.

    • getPredicateIndex

      public int getPredicateIndex()
      Get which predicate is executing.
      Returns:
      The current predicate index, or -1 if no predicate is executing.

    • fixupVariables

      public void fixupVariables​(Vector vars, int globalsSize)
      This function is used to fixup variables from QNames to stack frame indexes at stylesheet build time.
      Overrides:
      fixupVariables in class NodeTest
      Parameters:
      vars - List of QNames that correspond to variables. This list should be searched backwards for the first qualified name that corresponds to the variable reference qname. The position of the QName in the vector from the start of the vector will be its position in the stack frame (but variables above the globalsTop value will need to be offset to the current stack frame).

    • nodeToString

      protected String nodeToString​(int n)
      Diagnostics.
      Parameters:
      n - Node to give diagnostic information about, or null.
      Returns:
      Informative string about the argument.

    • acceptNode

      public short acceptNode​(int n)
      Test whether a specified node is visible in the logical view of a TreeWalker or NodeIterator. This function will be called by the implementation of TreeWalker and NodeIterator; it is not intended to be called directly from user code.
      Parameters:
      n - The node to check to see if it passes the filter or not.
      Returns:
      a constant to determine whether the node is accepted, rejected, or skipped, as defined above .

    • getLocPathIterator

      public LocPathIterator getLocPathIterator()
      Get the owning location path iterator.
      Returns:
      the owning location path iterator, which should not be null.

    • setLocPathIterator

      public void setLocPathIterator​(LocPathIterator li)
      Set the location path iterator owner for this walker. Besides initialization, this function is called during cloning operations.
      Parameters:
      li - non-null reference to the owning location path iterator.

    • canTraverseOutsideSubtree

      public boolean canTraverseOutsideSubtree()
      Tell if this expression or it's subexpressions can traverse outside the current subtree.
      Overrides:
      canTraverseOutsideSubtree in class Expression
      Returns:
      true if traversal outside the context node's subtree can occur.

    • callPredicateVisitors

      public void callPredicateVisitors​(XPathVisitor visitor)
      This will traverse the heararchy, calling the visitor for each member. If the called visitor method returns false, the subtree should not be called.
      Parameters:
      visitor - The visitor whose appropriate method will be called.

    • deepEquals

      public boolean deepEquals​(Expression expr)
      Description copied from class: Expression
      Compare this object with another object and see if they are equal, include the sub heararchy.
      Overrides:
      deepEquals in class NodeTest
      Parameters:
      expr - Another expression object.
      Returns:
      true if this objects class and the expr object's class are the same, and the data contained within both objects are considered equal.
      See Also:
      Expression.deepEquals(Expression)