Class AxisIteratorImpl

java.lang.Object
net.sf.saxon.tree.iter.AxisIteratorImpl
All Implemented Interfaces:
SequenceIterator, AxisIterator, UnfailingIterator
Direct Known Subclasses:
AncestorEnumeration, AttributeEnumeration, AttributeEnumeration, DescendantEnumeration, FollowingEnumeration, Navigator.AxisFilter, Navigator.BaseEnumeration, Navigator.EmptyTextFilter, PrecedingEnumeration, PrecedingSiblingEnumeration, SiblingEnumeration

public abstract class AxisIteratorImpl extends Object implements AxisIterator
A SequenceIterator is used to iterate over a sequence. An AxisIterator is a SequenceIterator that always iterates over a set of nodes, and that throws no exceptions; it also supports the ability to find the last() position, again with no exceptions. This class is an abstract implementation of AxisIterator that is used as a base class for many concrete implementations. The main functionality that it provides is maintaining the current position.
  • Field Details

    • position

      protected int position
    • current

      protected NodeInfo current
  • Constructor Details

    • AxisIteratorImpl

      public AxisIteratorImpl()
  • Method Details

    • moveNext

      public boolean moveNext()
      Move to the next node, without returning it. Returns true if there is a next node, false if the end of the sequence has been reached. After calling this method, the current node may be retrieved using the current() function.
      Specified by:
      moveNext in interface AxisIterator
      Returns:
      true if there is a next node, false if the end of the sequence has been reached
    • current

      public NodeInfo current()
      Get the current node in the sequence.
      Specified by:
      current in interface AxisIterator
      Specified by:
      current in interface SequenceIterator
      Specified by:
      current in interface UnfailingIterator
      Returns:
      the node returned by the most recent call on next()
    • position

      public final int position()
      Get the current position
      Specified by:
      position in interface SequenceIterator
      Specified by:
      position in interface UnfailingIterator
      Returns:
      the position of the most recent node returned by next()
    • close

      public void close()
      Description copied from interface: SequenceIterator
      Close the iterator. This indicates to the supplier of the data that the client does not require any more items to be delivered by the iterator. This may enable the supplier to release resources. After calling close(), no further calls on the iterator should be made; if further calls are made, the effect of such calls is undefined.

      (Currently, closing an iterator is important only when the data is being "pushed" in another thread. Closing the iterator terminates that thread and means that it needs to do no additional work. Indeed, failing to close the iterator may cause the push thread to hang waiting for the buffer to be emptied.)

      Specified by:
      close in interface SequenceIterator
    • iterateAxis

      public AxisIterator iterateAxis(byte axis, NodeTest test)
      Return an iterator over an axis, starting at the current node.
      Specified by:
      iterateAxis in interface AxisIterator
      Parameters:
      axis - the axis to iterate over, using a constant such as Axis.CHILD
      test - a predicate to apply to the nodes before returning them.
      Returns:
      an iterator over an axis, starting at the current node
    • atomize

      public Value atomize() throws XPathException
      Return the atomized value of the current node.
      Specified by:
      atomize in interface AxisIterator
      Returns:
      the atomized value.
      Throws:
      NullPointerException - if there is no current node
      XPathException - if the current node cannot be atomized, for example because it is an element node with element-only content.
    • getStringValue

      public CharSequence getStringValue()
      Return the string value of the current node.
      Specified by:
      getStringValue in interface AxisIterator
      Returns:
      the string value, as an instance of CharSequence.
      Throws:
      NullPointerException - if there is no current node
    • getProperties

      public int getProperties()
      Get properties of this iterator, as a bit-significant integer.
      Specified by:
      getProperties in interface SequenceIterator
      Returns:
      the properties of this iterator. This will be some combination of properties such as SequenceIterator.GROUNDED, SequenceIterator.LAST_POSITION_FINDER, and SequenceIterator.LOOKAHEAD. It is always acceptable to return the value zero, indicating that there are no known special properties. It is acceptable for the properties of the iterator to change depending on its state.