net.sf.saxon.tree.iter
Interface AxisIterator<T extends NodeInfo>

All Superinterfaces:

SequenceIterator<T>, UnfailingIterator<T>

All Known Implementing Classes:

AxisIteratorImpl, AxisIteratorOverSequence, EmptyAxisIterator, Navigator.AncestorEnumeration, Navigator.AxisFilter, Navigator.BaseEnumeration, Navigator.DescendantEnumeration, Navigator.EmptyTextFilter, Navigator.FollowingEnumeration, Navigator.PrecedingEnumeration, NodeWrappingAxisIterator, PrependIterator, SingleNodeIterator, VirtualCopy.VirtualCopier, VirtualUntypedCopy.VirtualUntypedCopier, WrappingIterator

public interface AxisIterator<T extends NodeInfo>
extends UnfailingIterator<T>

A SequenceIterator is used to iterate over a sequence. An AxisIterator is a SequenceIterator that throws no exceptions, and that always returns nodes. The nodes should all be in the same document (though there are some cases, such as PrependIterator, where this is the responsibility of the user of the class and is not enforced.)

Field Summary

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

GROUNDED, LAST_POSITION_FINDER, LOOKAHEAD

Method Summary

Value	atomize() Return the atomized value of the current node.
T	current() Get the current item in the sequence.
AxisIterator<T>	getAnother() Get another iterator over the same sequence of items, positioned at the start of the sequence.
CharSequence	getStringValue() Return the string value of the current node.
AxisIterator	iterateAxis(byte axis, NodeTest test) Return an iterator over an axis, starting at the current node.
boolean	moveNext() Move to the next node, without returning it.
T	next() Get the next item in the sequence.

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

position

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

close, getProperties

Method Detail

moveNext

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.

Returns:

true if there is a next node, false if the end of the sequence has been reached

next

T next()

Description copied from interface: UnfailingIterator

Get the next item in the sequence.

Specified by:

next in interface SequenceIterator<T extends NodeInfo>

Specified by:

next in interface UnfailingIterator<T extends NodeInfo>

Returns:

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

current

T current()

Description copied from interface: UnfailingIterator

Get the current item in the sequence.

Specified by:

current in interface SequenceIterator<T extends NodeInfo>

Specified by:

current in interface UnfailingIterator<T extends NodeInfo>

Returns:

the current item, that is, the item most recently returned by next()

getAnother

AxisIterator<T> getAnother()

Description copied from interface: UnfailingIterator

Get another iterator over the same sequence of items, positioned at the start of the sequence. It must be possible to call this method at any time, whether none, some, or all of the items in the original iterator have been read. The method is non-destructive: it does not change the state of the original iterator.

Specified by:

getAnother in interface SequenceIterator<T extends NodeInfo>

Specified by:

getAnother in interface UnfailingIterator<T extends NodeInfo>

Returns:

a new iterator over the same sequence

iterateAxis

AxisIterator iterateAxis(byte axis,
                         NodeTest test)

Return an iterator over an axis, starting at the current node.

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

Throws:

NullPointerException - if there is no current node

atomize

Value atomize()
              throws XPathException

Return the atomized value of the current node.

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

CharSequence getStringValue()

Return the string value of the current node.

Returns:

the string value, as an instance of CharSequence.

Throws:

NullPointerException - if there is no current node