net.sf.saxon.expr
Class FilterIterator.Leading

java.lang.Object
  net.sf.saxon.expr.FilterIterator
      net.sf.saxon.expr.FilterIterator.Leading

All Implemented Interfaces:

SequenceIterator

Enclosing class:

FilterIterator

public static final class FilterIterator.Leading
extends FilterIterator

Subclass to support the extension function saxon:leading, which terminates the iteration at the first item whose predicate is false

Nested Class Summary

Nested classes/interfaces inherited from class net.sf.saxon.expr.FilterIterator

FilterIterator.Leading, FilterIterator.NonNumeric

Field Summary

Fields inherited from class net.sf.saxon.expr.FilterIterator

base, filter, filterContext

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

GROUNDED, LAST_POSITION_FINDER, LOOKAHEAD

Constructor Summary

FilterIterator.Leading(SequenceIterator base, Expression filter, XPathContext context)
Create a FilterIterate that terminates at the first item for which the predicate evaluates to false

Method Summary

SequenceIterator	getAnother() Get another iterator to return the same nodes
protected Item	getNextMatchingItem() Get the next node that matches the filter predicate if there is one
protected boolean	matches() Determine whether the context item matches the filter predicate

Methods inherited from class net.sf.saxon.expr.FilterIterator

close, current, getProperties, next, position

Methods inherited from class java.lang.Object

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

Constructor Detail

FilterIterator.Leading

public FilterIterator.Leading(SequenceIterator base,
                              Expression filter,
                              XPathContext context)

Create a FilterIterate that terminates at the first item for which the predicate evaluates to false

Parameters:

base - iterator over the sequence to be filtered

filter - the filter expression - always evaluated as a boolean

context - the outer context for the filter expression as a whole; a new context will be created for evaluating the predicate

Method Detail

matches

protected boolean matches()
                   throws XPathException

Determine whether the context item matches the filter predicate

Overrides:

matches in class FilterIterator

Returns:

true if the context item matches

Throws:

XPathException

getNextMatchingItem

protected Item getNextMatchingItem()
                            throws XPathException

Get the next node that matches the filter predicate if there is one

Overrides:

getNextMatchingItem in class FilterIterator

Returns:

the next item that matches the predicate

Throws:

XPathException

getAnother

public SequenceIterator getAnother()
                            throws XPathException

Get another iterator to return the same nodes

Specified by:

getAnother in interface SequenceIterator

Overrides:

getAnother in class FilterIterator

Returns:

a SequenceIterator that iterates over the same items, positioned before the first item

Throws:

XPathException - if any error occurs