Package net.sf.saxon.event

Class NamespaceDifferencer

java.lang.Object

net.sf.saxon.event.SequenceReceiver

net.sf.saxon.event.ProxyReceiver

net.sf.saxon.event.NamespaceDifferencer

All Implemented Interfaces:

javax.xml.transform.Result, Receiver

public class NamespaceDifferencer
extends ProxyReceiver

NamespaceDifferencer is a ProxyReceiver responsible for removing duplicate namespace declarations. It also ensures that namespace undeclarations are emitted when necessary.

The NamespaceDifferencer assumes that in the input event stream, all in-scope namespaces for every element are accounted for in the call on namespace(). In the output event stream, the namespace() call represents namespace declarations rather than in-scope namespaces. So (a) redundant namespaces are removed, and (b) namespace undeclarations are added where necessary. A namespace undeclaration for the default namespace is always added if the parent element has a default namespace and the child element does not; namespace undeclarations for other namespaces are emitted only when the serialization option undeclare-namespaces is set.

The NamespaceDifferencer is part of the serialization pipeline, responsible for translating result trees to serialized XML. As such, it is not concerned with operations such as namespace fixup and namespace inheritance that are part of the result tree construction process.

The NamespaceDifferencer is also needed when writing output to tree models such as DOM and JDOM that require local namespace declarations to be provided for each element node.

Field Summary

Fields inherited from class net.sf.saxon.event.ProxyReceiver

nextReceiver

Fields inherited from class net.sf.saxon.event.SequenceReceiver

pipelineConfiguration, previousAtomic, systemId

Fields inherited from interface javax.xml.transform.Result

PI_DISABLE_OUTPUT_ESCAPING, PI_ENABLE_OUTPUT_ESCAPING

Constructor Summary

Constructors

Constructor	Description
NamespaceDifferencer(Receiver next, java.util.Properties details)	Create a NamespaceDeclarer

Method Summary

Modifier and Type	Method	Description
void	endElement()	End of element
void	startElement(NodeName elemName, SchemaType type, AttributeMap attributes, NamespaceMap namespaces, Location location, int properties)	startElement.

Methods inherited from class net.sf.saxon.event.ProxyReceiver

append, characters, close, comment, endDocument, getNamePool, getNextReceiver, open, processingInstruction, setPipelineConfiguration, setSystemId, setUnderlyingReceiver, setUnparsedEntity, startDocument, usesTypeAnnotations

Methods inherited from class net.sf.saxon.event.SequenceReceiver

append, decompose, flatten, getConfiguration, getErrorCodeForDecomposingFunctionItems, getPipelineConfiguration, getSystemId, handlesAppend

Methods inherited from class java.lang.Object

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

Constructor Detail

NamespaceDifferencer

public NamespaceDifferencer(Receiver next,
                            java.util.Properties details)

Create a NamespaceDeclarer

Parameters:

next - the Receiver to which events will be passed after namespace reduction

Method Detail

startElement

public void startElement(NodeName elemName,
                         SchemaType type,
                         AttributeMap attributes,
                         NamespaceMap namespaces,
                         Location location,
                         int properties)
                  throws XPathException

startElement. This call removes redundant namespace declarations, and possibly adds an xmlns="" undeclaration.

Specified by:

startElement in interface Receiver

Overrides:

startElement in class ProxyReceiver

Parameters:

elemName - the name of the element.

type - the type annotation of the element.

attributes - the attributes of this element

namespaces - the in-scope namespaces of this element: generally this is all the in-scope namespaces, without relying on inheriting namespaces from parent elements

location - an object providing information about the module, line, and column where the node originated

properties - bit-significant properties of the element node. If there are no relevant properties, zero is supplied. The definitions of the bits are in class ReceiverOption

Throws:

XPathException - if an error occurs

endElement

public void endElement()
                throws XPathException

Description copied from class: ProxyReceiver

End of element

Specified by:

endElement in interface Receiver

Overrides:

endElement in class ProxyReceiver

Throws:

XPathException - if an error occurs