net.sf.saxon.tree.iter

Class ReverseListIterator<T extends Item>

java.lang.Object

net.sf.saxon.tree.iter.ReverseListIterator<T>

All Implemented Interfaces:

java.io.Closeable, java.lang.AutoCloseable, LastPositionFinder, SequenceIterator, LookaheadIterator, ReversibleIterator, UnfailingIterator

public class ReverseListIterator<T extends Item>
extends java.lang.Object
implements UnfailingIterator, ReversibleIterator, LookaheadIterator, LastPositionFinder

ReverseListIterator is used to enumerate items held in an array in reverse order.

Author:

Michael H. Kay

Nested Class Summary

Nested classes/interfaces inherited from interface net.sf.saxon.om.SequenceIterator

SequenceIterator.Property

Constructor Summary

Constructors

Constructor and Description
ReverseListIterator(java.util.List<T> items) Create an iterator a slice of an array

Method Summary

Modifier and Type	Method and Description
int	getLength() Get the last position (that is, the number of items in the sequence).
java.util.EnumSet<SequenceIterator.Property>	getProperties() Get properties of this iterator, as a bit-significant integer.
SequenceIterator	getReverseIterator() Get an iterator that processes the same items in reverse order.
boolean	hasNext() Determine whether there are more items to come.
T	next() Get the next item in the sequence.

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.tree.iter.UnfailingIterator

forEach, toList

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

close, forEachOrFail, materialize

Constructor Detail

ReverseListIterator

public ReverseListIterator(java.util.List<T> items)

Create an iterator a slice of an array

Parameters:

items - The list of items

Method Detail

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

Returns:

true if there are more items in the sequence

next

public T next()

Description copied from interface: UnfailingIterator

Get the next item in the sequence.

Specified by:

next in interface SequenceIterator

Specified by:

next in interface UnfailingIterator

Returns:

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

getLength

public int getLength()

Description copied from interface: LastPositionFinder

Get the last position (that is, the number of items in the sequence). This method is non-destructive: it does not change the state of the iterator. The result is undefined if the next() method of the iterator has already returned null. This method must not be called unless the result of getProperties() on the iterator includes the bit setting SequenceIterator.Property.LAST_POSITION_FINDER

Specified by:

getLength in interface LastPositionFinder

Returns:

the number of items in the sequence

getProperties

public java.util.EnumSet<SequenceIterator.Property> 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.Property.GROUNDED, SequenceIterator.Property.LAST_POSITION_FINDER, and SequenceIterator.Property.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.

getReverseIterator

public SequenceIterator getReverseIterator()

Get an iterator that processes the same items in reverse order. Since this iterator is processing the items backwards, this method returns an ArrayIterator that processes them forwards.

Specified by:

getReverseIterator in interface ReversibleIterator

Returns:

a new ArrayIterator