Package net.sf.saxon.tree.linked

Class TreeEnumeration

java.lang.Object

net.sf.saxon.tree.linked.TreeEnumeration

All Implemented Interfaces:

Closeable, AutoCloseable, SequenceIterator<NodeInfo>, AxisIterator, LookaheadIterator<NodeInfo>, UnfailingIterator<NodeInfo>

Direct Known Subclasses:

AncestorEnumeration, ChildEnumeration, FollowingEnumeration, FollowingSiblingEnumeration, PrecedingEnumeration, PrecedingOrAncestorEnumeration, PrecedingSiblingEnumeration

abstract class TreeEnumeration
extends Object
implements AxisIterator, LookaheadIterator<NodeInfo>

Field Summary

Fields

Modifier and Type	Field	Description
protected NodeImpl	current
protected NodeImpl	next
protected NodeTest	nodeTest
protected int	position
protected NodeImpl	start

Fields inherited from interface net.sf.saxon.om.SequenceIterator

ATOMIZING, GROUNDED, LAST_POSITION_FINDER, LOOKAHEAD

Constructor Summary

Constructors

Constructor	Description
TreeEnumeration(NodeImpl origin, NodeTest nodeTest)	Create an axis enumeration for a given type and name of node, from a given origin node

Method Summary

Modifier and Type	Method	Description
protected void	advance()	Advance along the axis until a node is found that matches the required criteria
void	close()	Indicate that no more items are required from the iterator
protected boolean	conforms(NodeImpl node)	Test whether a node conforms to the node type and name constraints.
int	getProperties()	Get properties of this iterator, as a bit-significant integer.
boolean	hasNext()	Determine whether there are more items to come.
NodeInfo	next()	Return the next node in the sequence
protected abstract void	step()	Advance one step along the axis: the resulting node might not meet the required criteria for inclusion

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface net.sf.saxon.om.SequenceIterator

forEachOrFail, materialize

Methods inherited from interface net.sf.saxon.tree.iter.UnfailingIterator

firstWith, forEach, toGroundedValue, toList

Field Detail

start

protected NodeImpl start

next

protected NodeImpl next

nodeTest

protected NodeTest nodeTest

current

protected NodeImpl current

position

protected int position

Constructor Detail

TreeEnumeration

public TreeEnumeration(NodeImpl origin,
                       NodeTest nodeTest)

Create an axis enumeration for a given type and name of node, from a given origin node

Parameters:

origin - the node from which the axis originates

nodeTest - test to be satisfied by the returned nodes, or null if all nodes are to be returned.

Method Detail

conforms

protected boolean conforms(NodeImpl node)

Test whether a node conforms to the node type and name constraints. Note that this returns true if the supplied node is null, this is a way of terminating a loop.

Parameters:

node - the node to be tested

Returns:

true if the node matches the requested node type and name

advance

protected final void advance()

Advance along the axis until a node is found that matches the required criteria

step

protected abstract void step()

Advance one step along the axis: the resulting node might not meet the required criteria for inclusion

hasNext

public boolean hasNext()

Determine whether there are more items to come. Note that this operation is stateless and it is not necessary (or usual) to call it before calling next(). It is used only when there is an explicit need to tell if we are at the last element.

Specified by:

hasNext in interface LookaheadIterator<NodeInfo>

Returns:

true if there are more items in the sequence

next

public final NodeInfo next()

Return the next node in the sequence

Specified by:

next in interface AxisIterator

Specified by:

next in interface SequenceIterator<NodeInfo>

Specified by:

next in interface UnfailingIterator<NodeInfo>

Returns:

the next Item. If there are no more items, return null.

close

public void close()

Indicate that no more items are required from the iterator

Specified by:

close in interface AutoCloseable

Specified by:

close in interface Closeable

Specified by:

close in interface SequenceIterator<NodeInfo>

getProperties

public int getProperties()

Get properties of this iterator, as a bit-significant integer.

Specified by:

getProperties in interface SequenceIterator<NodeInfo>

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.