com.saxonica.ee.stream.feed

Class NoOpenOrCloseFeed

java.lang.Object

com.saxonica.ee.stream.feed.ItemFeed

com.saxonica.ee.stream.feed.NoOpenOrCloseFeed

All Implemented Interfaces:

Feed

public class NoOpenOrCloseFeed
extends ItemFeed

This feed is used for the inner loop of a for-each, where the results of multiple iterations need to be concatenated into a single sequence. This means we don't want a call on open/close around each inner iteration. So this feed suppresses these calls, preventing them cascading up the pipeline.

Constructor Summary

Constructors

Constructor and Description
NoOpenOrCloseFeed(Feed parentFeed, XPathContext context)

Method Summary

Methods

Modifier and Type	Method and Description
void	close() Finish evaluating the expression.
void	endSelectedParentNode(int locationId) Signal that the endElement event has occurred for the element whose startElement event caused the Watch to be activated.
void	open(Terminator terminator) Start evaluating the expression.
void	processItem(Item item) Supply one item towards the streamed input of the expression
Receiver	startSelectedParentNode(FleetingParentNode node, int locationId) Signal that an element or document node has been found that matches the selection that this Watch is looking for.

Methods inherited from class com.saxonica.ee.stream.feed.ItemFeed

dynamicError, getContext, getExpression, getPipelineConfiguration, getReceiver, getResult, getTerminator, hasFailed, processItems, setExpression, setHasFailed, setPipelineConfiguration, setTerminator

Methods inherited from class java.lang.Object

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

Constructor Detail

NoOpenOrCloseFeed

public NoOpenOrCloseFeed(Feed parentFeed,
                 XPathContext context)

Method Detail

open

public void open(Terminator terminator)

Description copied from class: ItemFeed

Start evaluating the expression. The default implementation does nothing.

Specified by:

open in interface Feed

Overrides:

open in class ItemFeed

Parameters:

terminator - used to achieve early exit

startSelectedParentNode

public Receiver startSelectedParentNode(FleetingParentNode node,
                               int locationId)
                                 throws XPathException

Description copied from class: ItemFeed

Signal that an element or document node has been found that matches the selection that this Watch is looking for. This method is called by the WatchManager while processing the startElement or startDocument event that matches the selection.

Specified by:

startSelectedParentNode in interface Feed

Overrides:

startSelectedParentNode in class ItemFeed

Parameters:

node - the element or document node whose start event has been matched

locationId - the location associated with the element or document node (may be the location of the instruction that created it)

Returns:

a Receiver to be notified of all events starting with the startElement/startDocument event for the matched element, and ending with the endElement event for that element; or null if this feature is not required.

Throws:

XPathException - May be raised if a dynamic error occurs

processItem

public void processItem(Item item)
                 throws XPathException

Description copied from class: ItemFeed

Supply one item towards the streamed input of the expression

Specified by:

processItem in interface Feed

Specified by:

processItem in class ItemFeed

Parameters:

item - the item to be supplied

Throws:

XPathException - May be raised if a dynamic error occurs

endSelectedParentNode

public void endSelectedParentNode(int locationId)
                           throws XPathException

Description copied from class: ItemFeed

Signal that the endElement event has occurred for the element whose startElement event caused the Watch to be activated.

Specified by:

endSelectedParentNode in interface Feed

Overrides:

endSelectedParentNode in class ItemFeed

Parameters:

locationId - the location of the element

Throws:

XPathException - May be raised if a constraint implemented by this Watch is violated

close

public void close()

Description copied from class: ItemFeed

Finish evaluating the expression. The default implementation does nothing.

Specified by:

close in interface Feed

Overrides:

close in class ItemFeed