Package org.apache.xalan.xsltc.dom

Class MatchingIterator

java.lang.Object
org.apache.xml.dtm.ref.DTMAxisIteratorBase
org.apache.xalan.xsltc.dom.MatchingIterator
All Implemented Interfaces:
Cloneable, DTMAxisIterator
public final class MatchingIterator extends DTMAxisIteratorBase
This is a special kind of iterator that takes a source iterator and a node N. If initialized with a node M (the parent of N) it computes the position of N amongst the children of M. This position can be obtained by calling getPosition(). It is an iterator even though next() will never be called. It is used to match patterns with a single predicate like: BOOK[position() = last()] In this example, the source iterator will return elements of type BOOK, a call to position() will return the position of N. Notice that because of the way the pattern matching is implemented, N will always be a node in the source since (i) it is a BOOK or the test sequence would not be considered and (ii) the source iterator is initialized with M which is the parent of N. Also, and still in this example, a call to last() will return the number of elements in the source (i.e. the number of BOOKs).
Author:
Jacek Ambroziak, Santiago Pericas-Geertsen

  • Constructor Details

    • MatchingIterator

      public MatchingIterator(int match, DTMAxisIterator source)

  • Method Details

    • setRestartable

      public void setRestartable(boolean isRestartable)
      Description copied from interface: DTMAxisIterator
      Set if restartable.
      Specified by:
      setRestartable in interface DTMAxisIterator
      Overrides:
      setRestartable in class DTMAxisIteratorBase

    • cloneIterator

      public DTMAxisIterator cloneIterator()
      Description copied from class: DTMAxisIteratorBase
      Returns a deep copy of this iterator. Cloned iterators may not be restartable. The iterator being cloned may or may not become non-restartable as a side effect of this operation.
      Specified by:
      cloneIterator in interface DTMAxisIterator
      Overrides:
      cloneIterator in class DTMAxisIteratorBase
      Returns:
      a deep copy of this iterator.

    • setStartNode

      public DTMAxisIterator setStartNode(int node)
      Description copied from interface: DTMAxisIterator
      Set start to END should 'close' the iterator, i.e. subsequent call to next() should return END.
      Parameters:
      node - Sets the root of the iteration.
      Returns:
      A DTMAxisIterator set to the start of the iteration.

    • reset

      public DTMAxisIterator reset()
      Description copied from interface: DTMAxisIterator
      Resets the iterator to the last start node.
      Specified by:
      reset in interface DTMAxisIterator
      Overrides:
      reset in class DTMAxisIteratorBase
      Returns:
      A DTMAxisIterator which has been reset to the start node, which may or may not be the same as this iterator.

    • next

      public int next()
      Description copied from interface: DTMAxisIterator
      Get the next node in the iteration.
      Returns:
      The next node handle in the iteration, or END.

    • getLast

      public int getLast()
      Description copied from class: DTMAxisIteratorBase
      Returns the position of the last node within the iteration, as defined by XPath. In a forward iterator, I believe this equals the number of nodes which this iterator will yield. In a reverse iterator, I believe it should return 1 (since the "last" is the first produced.) This may be an expensive operation when called the first time, since it may have to iterate through a large part of the document to produce its answer.
      Specified by:
      getLast in interface DTMAxisIterator
      Overrides:
      getLast in class DTMAxisIteratorBase
      Returns:
      The number of nodes in this iterator (forward) or 1 (reverse).

    • getPosition

      public int getPosition()
      Specified by:
      getPosition in interface DTMAxisIterator
      Overrides:
      getPosition in class DTMAxisIteratorBase
      Returns:
      The position of the current node within the set, as defined by XPath. Note that this is one-based, not zero-based.

    • setMark

      public void setMark()
      Description copied from interface: DTMAxisIterator
      Remembers the current node for the next call to gotoMark().

    • gotoMark

      public void gotoMark()
      Description copied from interface: DTMAxisIterator
      Restores the current node remembered by setMark().