com.saxonica.ee.validate

Class SelectorWatch

java.lang.Object

com.saxonica.ee.stream.watch.AbstractWatch

com.saxonica.ee.stream.watch.PatternWatch

com.saxonica.ee.validate.SelectorWatch

All Implemented Interfaces:

Watch

Direct Known Subclasses:

KeySelectorWatch, RefSelectorWatch

public abstract class SelectorWatch
extends PatternWatch

A Watch represents a class that is interested in looking at nodes for the purpose of evaluating uniqueness and key constraints. A SelectorWatch looks for the nodes that match the selector in a unique, key, or keyref constraint. There are two concrete subclasses: one for key/unique, the other for keyref

Constructor Summary

Constructors

Constructor and Description
SelectorWatch(ConstraintChecker checker, IdentityConstraint uniqueConstraint)

Method Summary

Modifier and Type	Method and Description
void	addFieldValue(AtomicSequence[] currentRow, int column, AtomicSequence value, boolean nillableElement, Location locationId) The addFieldValue method is a callback from the FieldWatch created when this SelectorWatch is activated.
protected void	checkRow(AtomicSequence[] currentRow, boolean isTarget, Location locationId) Method to check that a row (that is, the collection of fields corresponding to one selected node) is valid.
void	close() The close() method is called immediately before the Watch is destroyed, that is, when the element whose declaration scopes the constraint implemented by this Watch goes out of scope.
void	endSelectedParentNode(Location locationId) Signal that the endElement event has occurred for the element whose startElement event caused the Watch to be activated.
IdentityConstraint	getIdentityConstraint() Get the identityConstraint implemented by this SelectorWatch
protected void	reportValidationError(ValidationFailure err, Location locator) Report a validation error
Receiver	startSelectedParentNode(FleetingParentNode node, Location locationId) Signal that an element has been found that matches the selection that this Watch is looking for.

Methods inherited from class com.saxonica.ee.stream.watch.PatternWatch

getAnchorNode, getSelection, matchesNode, matchesNodesOfKind, open, processItem, setAnchorNode, setSelection

Methods inherited from class com.saxonica.ee.stream.watch.AbstractWatch

getNamespaceResolver, getPipelineConfiguration, getReceiver, setNamespaceResolver, setPipelineConfiguration

Methods inherited from class java.lang.Object

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

Constructor Detail

SelectorWatch

public SelectorWatch(ConstraintChecker checker,
                     IdentityConstraint uniqueConstraint)

Method Detail

getIdentityConstraint

public IdentityConstraint getIdentityConstraint()

Get the identityConstraint implemented by this SelectorWatch

Returns:

the identity constraint

startSelectedParentNode

public Receiver startSelectedParentNode(FleetingParentNode node,
                                        Location 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 events for the subtree rooted at the element matched by this Watch. A SelectorWatch does not require such notification, so it returns null. @param locationId

Throws:

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

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 -

Throws:

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

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

close

public void close()
           throws XPathException

The close() method is called immediately before the Watch is destroyed, that is, when the element whose declaration scopes the constraint implemented by this Watch goes out of scope.

Specified by:

close in interface Watch

Overrides:

close in class PatternWatch

Throws:

XPathException - May be raised if a dynamic error occurs

addFieldValue

public void addFieldValue(AtomicSequence[] currentRow,
                          int column,
                          AtomicSequence value,
                          boolean nillableElement,
                          Location locationId)
                   throws XPathException

The addFieldValue method is a callback from the FieldWatch created when this SelectorWatch is activated. It indicates that a value for one of the fields participating in this constraint has been encountered.

Parameters:

currentRow - identifying the node to which this field value applies

column - identifies which of the fields participating in this constraint the value relates to

value - The value of the field that was encountered

nillableElement - True if the field represents a nillable element

locationId - the location of the data in the source document

Throws:

ValidationException - May be raised if the value of the field violates the constraint

XPathException

checkRow

protected void checkRow(AtomicSequence[] currentRow,
                        boolean isTarget,
                        Location locationId)
                 throws XPathException

Method to check that a row (that is, the collection of fields corresponding to one selected node) is valid.

Parameters:

currentRow - the values of the set of fields

isTarget - set to true if this is a value of the key referred to by a key reference, rather than a value for this constraint's own selected fields.

locationId - identifies the location of the selected node

Throws:

ValidationException - is raised if the value of the row (that is, the combination of fields) violates the constraint

XPathException

reportValidationError

protected void reportValidationError(ValidationFailure err,
                                     Location locator)
                              throws XPathException

Report a validation error

Parameters:

err - The validation exception

locator - identifies the location in the source document or stylesheet/query where the validation error was detected

Throws:

ValidationException - if the threshold on number of errors is exceeded

XPathException