com.saxonica.ee.stream.feed

Class MotionlessFeed

java.lang.Object

net.sf.saxon.event.Outputter

net.sf.saxon.event.ProxyOutputter

com.saxonica.ee.stream.feed.ItemFeed

com.saxonica.ee.stream.feed.MotionlessFeed

All Implemented Interfaces:

javax.xml.transform.Result, Receiver

public class MotionlessFeed
extends ItemFeed

A feed for an expression that typically accesses the context item but does not consume the input stream. This class only ever appears as the first thing triggered by a watch. It evaluates the non-consuming expression immediately when the start event is reported, supplying the items that result from the evaluation to the next feed in the pipeline.

Field Summary

Fields inherited from class net.sf.saxon.event.Outputter

pipelineConfiguration, systemId

Fields inherited from interface javax.xml.transform.Result

PI_DISABLE_OUTPUT_ESCAPING, PI_ENABLE_OUTPUT_ESCAPING

Constructor Summary

Constructors

Constructor and Description
MotionlessFeed(Expression expression, ItemFeed result, XPathContext context)

Method Summary

Modifier and Type	Method and Description
void	append(Item item) Supply one item towards the streamed input of the expression
void	endSelectedParentNode(Location locationId) Signal that the endElement event has occurred for the element whose startElement event caused the Watch to be activated.
Receiver	startSelectedParentNode(FleetingParentNode node, Location 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

append, close, dynamicError, getContext, getExpression, getResultFeed, getTerminator, hasFailed, open, processItems, setExpression, setHasFailed, setTerminator

Methods inherited from class net.sf.saxon.event.ProxyOutputter

attribute, characters, comment, endDocument, endElement, getNextOutputter, namespace, open, processingInstruction, setUnparsedEntity, startContent, startDocument, startElement, startElement, usesTypeAnnotations

Methods inherited from class net.sf.saxon.event.Outputter

getConfiguration, getPipelineConfiguration, getStringReceiver, getSystemId, namespaces, setPipelineConfiguration, setSystemId

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.event.Receiver

handlesAppend

Constructor Detail

MotionlessFeed

public MotionlessFeed(Expression expression,
                      ItemFeed result,
                      XPathContext context)

Method Detail

startSelectedParentNode

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

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.

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

append

public void append(Item item)
            throws XPathException

Supply one item towards the streamed input of the expression

Specified by:

append in interface Receiver

Specified by:

append in class ItemFeed

Parameters:

item - the item to be supplied

Throws:

XPathException - if the operation fails

endSelectedParentNode

public void endSelectedParentNode(Location 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.

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