Package org.loboevolution.apache.xpath.axes

Class WalkingIterator

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.WalkingIterator
All Implemented Interfaces:
Cloneable, SourceLocator, DTMIterator, PathComponent, SubContextList, ExpressionNode, XPathVisitable
Direct Known Subclasses:
WalkingIteratorSorted
public class WalkingIterator extends LocPathIterator
Location path iterator that uses Walkers.

  • Field Details

    • m_lastUsedWalker

      protected AxesWalker m_lastUsedWalker
      The last used step walker in the walker list.

    • m_firstWalker

      protected AxesWalker m_firstWalker
      The head of the step walker list.

  • Constructor Details

    • WalkingIterator

      public WalkingIterator(PrefixResolver nscontext)
      Create a WalkingIterator object.
      Parameters:
      nscontext - The namespace context for this iterator, should be OK if null.

  • Method Details

    • getAnalysisBits

      public int getAnalysisBits()
      Get the analysis bits for this path component, as defined in the WalkerFactory.
      Specified by:
      getAnalysisBits in interface PathComponent
      Overrides:
      getAnalysisBits in class LocPathIterator
      Returns:
      One of WalkerFactory#BIT_DESCENDANT, etc.

    • clone

      public Object clone() throws CloneNotSupportedException
      Specified by:
      clone in interface DTMIterator
      Overrides:
      clone in class PredicatedNodeTest
      Returns:
      A clone of this object.
      Throws:
      CloneNotSupportedException - if any

    • reset

      public void reset()
      Reset the iterator to the start. After resetting, the next node returned will be the root node -- or, if that's filtered out, the first node within the root's subtree which is _not_ skipped by the filters.
      Specified by:
      reset in interface DTMIterator
      Overrides:
      reset in class LocPathIterator

    • 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.

    • 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.

    • setLastUsedWalker

      public final void setLastUsedWalker(AxesWalker walker)
      Set the last used walker.
      Parameters:
      walker - The last used walker, or null.

    • getLastUsedWalker

      public final AxesWalker getLastUsedWalker()
      Get the last used walker.
      Returns:
      The last used walker, or null.

    • 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

    • callVisitors

      public void callVisitors(XPathVisitor visitor)
      This will traverse the hierarchy, calling the visitor for each member. If the called visitor method returns false, the subtree should not be called.
      Specified by:
      callVisitors in interface XPathVisitable
      Overrides:
      callVisitors in class LocPathIterator
      Parameters:
      visitor - The visitor whose appropriate method will be called.

    • 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.