com.saxonica.stream.watch
Class SimpleContentWatch

java.lang.Object
  extended by com.saxonica.validate.AbstractWatch
      extended by com.saxonica.stream.watch.ComposingWatch
          extended by com.saxonica.stream.watch.SimpleContentWatch
All Implemented Interfaces:
Watch

public class SimpleContentWatch
extends ComposingWatch
implements Watch

This class is used when a streaming template requests evaluation of a simple content constructor in streaming mode (that is, when it constructs a text, attribute, comment, or PI node based on the contents of the streamed document). The result of this Watch is a single string, constructed using the rules of "Constructing Simple Content" in the XSLT specification.

The AdjacentTextNodeMergerFeed is used when the node is constructed as a result of a computation on the streamed data, for example xsl:value-of select="distinct-values(.//@price)". By contrast, a SimpleContentWatch is used when the streamed nodes are selected directly, for example xsl:value-of select=".//@price".

Both a Feed and a Watch are needed because a simple content constructor operates on a sequence of nodes without simply atomizing the sequence.


Constructor Summary
SimpleContentWatch(Feed result, Stack<XPathContext> contextStack)
           
 
Method Summary
 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(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.stream.watch.ComposingWatch
getContext, getContextStack, getResult, open
 
Methods inherited from class com.saxonica.validate.AbstractWatch
getAnchorNode, getNamespaceResolver, getPipelineConfiguration, getSelection, setAnchorNode, setNamespaceResolver, setPipelineConfiguration, setSelection
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 
Methods inherited from interface com.saxonica.stream.watch.Watch
getAnchorNode, getNamespaceResolver, getPipelineConfiguration, getSelection, open, setAnchorNode, setNamespaceResolver, setPipelineConfiguration, setSelection
 

Constructor Detail

SimpleContentWatch

public SimpleContentWatch(Feed result,
                          Stack<XPathContext> contextStack)
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

Specified by:
startSelectedParentNode in interface Watch
Parameters:
node -
locationId - @throws net.sf.saxon.type.ValidationException May be raised if the constraint implemented by this Watch is violated
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.
Throws:
ValidationException - May be raised if the constraint implemented by this Watch is violated
XPathException

endSelectedParentNode

public void endSelectedParentNode(int locationId)
                           throws XPathException
Signal that the endElement event has occurred for the element whose startElement event caused the Watch to be activated.

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

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 -
Throws:
XPathException

close

public final 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 ComposingWatch
Throws:
XPathException


Copyright (c) 2004-2011 Saxonica Limited. All rights reserved.