com.saxonica.ee.stream.watch

Class StreamWatch

java.lang.Object

com.saxonica.ee.stream.watch.AbstractWatch

com.saxonica.ee.stream.watch.StreamWatch

All Implemented Interfaces:

Watch

public class StreamWatch
extends AbstractWatch

Constructor Summary

Constructors

Constructor and Description
StreamWatch(Inversion action, WatchManager watchManager, XPathContext context)

Method Summary

Modifier and Type	Method and Description
void	endSelectedParentNode(Location locationId) Signal that the endElement event has occurred for the element whose startElement event caused the Watch to be activated.
FleetingParentNode	getAnchorNode() Get the anchor node for the watch.
boolean	matchesNode(FleetingNode node, XPathContext context) Determine whether the watch matches a given node
boolean	matchesNodesOfKind(UType kind) Ask whether the Watch is capable of matching nodes of a particular kind
void	setAnchorNode(FleetingParentNode anchor) Set the anchor node for the watch.
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.watch.AbstractWatch

close, getNamespaceResolver, getPipelineConfiguration, getReceiver, open, processItem, setNamespaceResolver, setPipelineConfiguration

Methods inherited from class java.lang.Object

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

Constructor Detail

StreamWatch

public StreamWatch(Inversion action,
                   WatchManager watchManager,
                   XPathContext context)

Method Detail

matchesNode

public boolean matchesNode(FleetingNode node,
                           XPathContext context)
                    throws XPathException

Determine whether the watch matches a given node

Parameters:

node - the node to be tested

context - the XPath dynamic context

Returns:

true if the node is one of those the Watch is looking out for

Throws:

XPathException - if a dynamic error occurs

matchesNodesOfKind

public boolean matchesNodesOfKind(UType kind)

Ask whether the Watch is capable of matching nodes of a particular kind

Parameters:

kind - the node kind

Returns:

true if the watch is capabl of matching

setAnchorNode

public void setAnchorNode(FleetingParentNode anchor)

Set the anchor node for the watch. This is the node to which the watch is scoped, typically the context node for the streamable path expression that defines the root of the subtree within which nodes are being sought.

Parameters:

anchor - The anchor node within which the watch is scoped

getAnchorNode

public FleetingParentNode getAnchorNode()

Get the anchor node for the watch. This is the node to which the watch is scoped, typically the context node for the streamable path expression that defines the root of the subtree within which nodes are being sought.

Returns:

The anchor node within which the watch is scoped

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.

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

endSelectedParentNode

public void endSelectedParentNode(Location locationId)
                           throws XPathException

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

Parameters:

locationId - the location of the element

Throws:

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