Package org.apache.xalan.xsltc.dom

Class MultiValuedNodeHeapIterator

java.lang.Object
org.apache.xml.dtm.ref.DTMAxisIteratorBase
org.apache.xalan.xsltc.dom.MultiValuedNodeHeapIterator
All Implemented Interfaces:
Cloneable, DTMAxisIterator
Direct Known Subclasses:
KeyIndex.KeyIndexIterator, UnionIterator
public abstract class MultiValuedNodeHeapIterator extends DTMAxisIteratorBase

MultiValuedNodeHeapIterator takes a set of multi-valued heap nodes and produces a merged NodeSet in document order with duplicates removed.

Each multi-valued heap node (which might be a DTMAxisIterator, but that's not necessary) generates DTM node handles in document order. The class maintains the multi-valued heap nodes in a heap, not surprisingly, sorted by the next DTM node handle available form the heap node.

After a DTM node is pulled from the heap node that's at the top of the heap, the heap node is advanced to the next DTM node handle it makes available, and the heap nature of the heap is restored to ensure the next DTM node handle pulled is next in document order overall.

Author:
Jacek Ambroziak, Santiago Pericas-Geertsen

  • Constructor Details

    • MultiValuedNodeHeapIterator

      public MultiValuedNodeHeapIterator()

  • Method Details

    • 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.

    • 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.

    • 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.

    • 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().

    • 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.