com.saxonica.ee.stream.feed

Class ItemMappingFeed

java.lang.Object

com.saxonica.ee.stream.feed.ItemFeed

com.saxonica.ee.stream.feed.ItemMappingFeed

All Implemented Interfaces:

Feed

public class ItemMappingFeed
extends ItemFeed

A Feed which applies an ItemMappingFunction to each supplied item. This produces zero or one output items for each input item. The ItemMappingFunction must be one that is capable of handling streamed nodes (otherwise an UnsupportedOperationException is likely).

Constructor Summary

Constructors

Constructor and Description
ItemMappingFeed(Expression expr, Feed result, XPathContext context, ItemMappingFunction<Item,? extends Item> function)

Method Summary

Methods

Modifier and Type	Method and Description
void	close() Finish evaluating the expression.
void	endSelectedParentNode(int locationId) Signal that the endElement event has occurred for the element whose startElement event caused the Watch to be activated.
void	processItem(Item item) Supply an item to the feed
Receiver	startSelectedParentNode(FleetingParentNode node, int 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.feed.ItemFeed

dynamicError, getContext, getExpression, getPipelineConfiguration, getReceiver, getResult, getTerminator, hasFailed, open, processItems, setExpression, setHasFailed, setPipelineConfiguration, setTerminator

Methods inherited from class java.lang.Object

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

Constructor Detail

ItemMappingFeed

public ItemMappingFeed(Expression expr,
               Feed result,
               XPathContext context,
               ItemMappingFunction<Item,? extends Item> function)

Method Detail

startSelectedParentNode

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

Description copied from class: ItemFeed

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.

Specified by:

startSelectedParentNode in interface Feed

Overrides:

startSelectedParentNode in class ItemFeed

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(int locationId)
                           throws XPathException

Description copied from class: ItemFeed

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

Specified by:

endSelectedParentNode in interface Feed

Overrides:

endSelectedParentNode in class ItemFeed

Parameters:

locationId - the location of the element

Throws:

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

processItem

public void processItem(Item item)
                 throws XPathException

Supply an item to the feed

Specified by:

processItem in interface Feed

Specified by:

processItem in class ItemFeed

Parameters:

item - the item being fed

Throws:

XPathException - to report any failure

close

public void close()
           throws XPathException

Finish evaluating the expression. The default implementation does nothing.

Specified by:

close in interface Feed

Overrides:

close in class ItemFeed

Throws:

XPathException - if a dynamic error occurs