Package org.loboevolution.apache.xpath.axes

Class DescendantIterator

java.lang.Object
org.loboevolution.apache.xpath.Expression
org.loboevolution.apache.xpath.patterns.NodeTest
org.loboevolution.apache.xpath.axes.PredicatedNodeTest
org.loboevolution.apache.xpath.axes.LocPathIterator
org.loboevolution.apache.xpath.axes.DescendantIterator
All Implemented Interfaces:
Cloneable, SourceLocator, DTMIterator, PathComponent, SubContextList, ExpressionNode, XPathVisitable
public class DescendantIterator extends LocPathIterator
This class implements an optimized iterator for descendant, descendant-or-self, or "//foo" patterns.
See Also:

  • Field Details

    • m_traverser

      protected transient DTMAxisTraverser m_traverser
      The traverser to use to navigate over the descendants.

    • m_axis

      protected int m_axis
      The axis that we are traversing.

    • m_extendedTypeID

      protected int m_extendedTypeID
      The extended type ID, not set until setRoot.

  • Method Details

    • cloneWithReset

      public DTMIterator cloneWithReset() throws CloneNotSupportedException
      Get a cloned Iterator that is reset to the start of the iteration.
      Specified by:
      cloneWithReset in interface DTMIterator
      Overrides:
      cloneWithReset in class LocPathIterator
      Returns:
      A clone of this iteration that has been reset.
      Throws:
      CloneNotSupportedException - if any

    • nextNode

      public int nextNode()
      Returns the next node in the set and advances the position of the iterator in the set. After a DTMIterator has setRoot called, the first call to nextNode() returns that root or (if it is rejected by the filters) the first node within its subtree which is not filtered out.
      Specified by:
      nextNode in interface DTMIterator
      Specified by:
      nextNode in class LocPathIterator
      Returns:
      The next node handle in the set being iterated over, or DTM.NULL if there are no more members in that set.

    • setRoot

      public void setRoot(int context, Object environment)
      Reset the root node of the DTMIterator, overriding the value specified when it was created. Note the root node is not the root node of the document tree, but the context node from where the iteration begins.
      Specified by:
      setRoot in interface DTMIterator
      Overrides:
      setRoot in class LocPathIterator
      Parameters:
      context - int Handle of the context node.
      environment - The environment object. The environment in which this iterator operates, which should provide:

      a node (the context node... same value as "root" defined below)

      a pair of non-zero positive integers (the context position and the context size)

      a set of variable bindings

      a function library

      the set of namespace declarations in scope for the expression.

      At this time the exact implementation of this environment is application dependent. Probably a proper interface will be created fairly soon.

    • asNode

      public int asNode(XPathContext xctxt) throws TransformerException
      Return the first node out of the nodeset, if this expression is a nodeset expression.
      Overrides:
      asNode in class LocPathIterator
      Parameters:
      xctxt - The XPath runtime context.
      Returns:
      the first node out of the nodeset, or DTM.NULL.
      Throws:
      TransformerException - if any

    • detach

      public void detach()
      Detaches the DTMIterator from the set which it iterated over, releasing any computational resources and placing the iterator in the INVALID state. After detach has been invoked, calls to nextNode or previousNode will raise a runtime exception.
      Specified by:
      detach in interface DTMIterator
      Overrides:
      detach in class LocPathIterator

    • getAxis

      public int getAxis()
      Returns the axis being iterated, if it is known.
      Specified by:
      getAxis in interface DTMIterator
      Overrides:
      getAxis in class LocPathIterator
      Returns:
      Axis.CHILD, etc., or -1 if the axis is not known or is of multiple types.

    • deepEquals

      public boolean deepEquals(Expression expr)
      Compare this object with another object and see if they are equal, include the sub heararchy.
      Overrides:
      deepEquals in class PredicatedNodeTest
      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.