com.saxonica.validate

Class FieldWatch

java.lang.Object

com.saxonica.validate.AbstractWatch

com.saxonica.validate.FieldWatch

All Implemented Interfaces:

Watch

public class FieldWatch
extends AbstractWatch

A FieldWatch is a class that is looking for nodes that match a field selector within a uniqueness or key constraint.

Constructor Summary

Constructors

Constructor and Description
FieldWatch(SelectorWatch parentWatch, Pattern selection, AtomicSequence[] currentRow, int column) Create a new FieldWatch

Method Summary

Methods

Modifier and Type	Method and Description
void	endSelectedParentNode(int locationId) Signal that the endElement event has occurred for the element whose startElement event caused the Watch to be activated.
void	notifySelectedLeafNode(FleetingNode node, int locationId) Signal that a node (other than an element) that matches the selection has been found.
Receiver	startSelectedParentNode(FleetingNode node, int locationId) Signal that an element has been found that matches the selection that this Watch is looking for.

Methods inherited from class com.saxonica.validate.AbstractWatch

close, getAnchorNode, getNamespaceResolver, getPipelineConfiguration, getSelection, open, setAnchorNode, setNamespaceResolver, setPipelineConfiguration, setSelection

Methods inherited from class java.lang.Object

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

Constructor Detail

FieldWatch

public FieldWatch(SelectorWatch parentWatch,
          Pattern selection,
          AtomicSequence[] currentRow,
          int column)

Create a new FieldWatch

Parameters:

parentWatch - The SelectorWatch to which field values should be notified

selection - The selection (that is, the restricted XPath expression) used in this field of the constraint

currentRow - represents the selected node whose fields are being evaluated

column - sequence number for this field within the constraint being evaluated

Method Detail

startSelectedParentNode

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

Signal that an element has been found that matches the selection that this Watch is looking for. This method is called by the ConstraintChecker while processing the startElement event that matches the selection. For this purpose, any attributes selected by the last step in the selection are ignored

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:

ValidationException - May be raised if the constraint implemented by this Watch is violated @param locationId

XPathException - May be raised if a dynamic error occurs

endSelectedParentNode

public void endSelectedParentNode(int locationId)
                           throws ValidationException

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:

ValidationException - May be raised if the constraint implemented by this Watch is violated @param locationId

notifySelectedLeafNode

public void notifySelectedLeafNode(FleetingNode node,
                          int locationId)
                            throws XPathException

Signal that a node (other than an element) that matches the selection has been found.

Specified by:

notifySelectedLeafNode in interface Watch

Overrides:

notifySelectedLeafNode in class AbstractWatch

Parameters:

node - the node that was matched.

locationId - location for error reporting purposes

Throws:

XPathException