com.saxonica.validate
Class SelectorWatch

java.lang.Object
  com.saxonica.validate.SelectorWatch

All Implemented Interfaces:

Watch

Direct Known Subclasses:

KeySelectorWatch, RefSelectorWatch

public abstract class SelectorWatch
extends Object
implements Watch

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

SelectorWatch(ConstraintChecker checker, IdentityConstraint uniqueConstraint)

Method Summary

Receiver	activate(int locationId) Signal that an element has been found that matches the selection that this Watch is looking for.
void	addFieldValue(Value[] currentRow, int column, Value value, boolean nillableElement, long locationId) The addFieldValue method is a callback from the FieldWatch created when this SelectorWatch is activated.
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	deactivate(int 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
int	getOriginDepth() Get the depth within the XML hierarchy of the element whose element declaration contains the unique/key/keyref constraint that this Watch implements
Selection	getSelection() Get the selection (that is, the restricted XPath expression) that defines the nodes that this Watch is looking for
void	setNamespaceResolver(NamespaceResolver resolver) Set a NamespaceResolver for use by the Watch
void	setOriginDepth(int depth) Set the depth within the XML hierarchy of the element whose element declaration contains the unique/key/keyref constraint that this Watch implements
void	setPipelineConfiguration(PipelineConfiguration pipe) Set the PipelineConfiguration in use

Methods inherited from class java.lang.Object

equals, 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

getSelection

public Selection getSelection()

Get the selection (that is, the restricted XPath expression) that defines the nodes that this Watch is looking for

Specified by:

getSelection in interface Watch

Returns:

the selection

setPipelineConfiguration

public void setPipelineConfiguration(PipelineConfiguration pipe)

Set the PipelineConfiguration in use

Specified by:

setPipelineConfiguration in interface Watch

Parameters:

pipe - the PipelineConfiguration in use

setNamespaceResolver

public void setNamespaceResolver(NamespaceResolver resolver)

Set a NamespaceResolver for use by the Watch

Specified by:

setNamespaceResolver in interface Watch

Parameters:

resolver - the namespace resolver to be used

setOriginDepth

public void setOriginDepth(int depth)

Set the depth within the XML hierarchy of the element whose element declaration contains the unique/key/keyref constraint that this Watch implements

Specified by:

setOriginDepth in interface Watch

Parameters:

depth - The depth at which the watch is scoped. This corresponds to the elementStackTop level in the controlling WatchHandler, for the startElement event that is the first level notified to the watch. For example, an xs:unique constraint declared on the outermost element of the document will have an origin depth of zero. For a FieldWatch, the origin depth is the difference between the level at which the SelectorWatch is scoped, and the level at which it was activated. This for a constraint defined at BOOKLIST level with select xpath="BOOK" and field xpath="ISBN", the constraint will be scoped at level zero, and activated at level one; the origin depth for the Field Watch will be one.

getOriginDepth

public int getOriginDepth()

Get the depth within the XML hierarchy of the element whose element declaration contains the unique/key/keyref constraint that this Watch implements

Specified by:

getOriginDepth in interface Watch

Returns:

The depth at which the watch is scoped

activate

public Receiver activate(int locationId)
                  throws ValidationException

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

Specified by:

activate in interface Watch

Parameters:

locationId - the location of the element

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

deactivate

public void deactivate(int locationId)
                throws ValidationException

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

Specified by:

deactivate in interface Watch

Parameters:

locationId - the location of the element

Throws:

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

close

public void close()
           throws ValidationException

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

Throws:

ValidationException

addFieldValue

public void addFieldValue(Value[] currentRow,
                          int column,
                          Value value,
                          boolean nillableElement,
                          long locationId)
                   throws ValidationException

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 -

locationId -

Throws:

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