net.sf.saxon.event

Class NamespaceReducer

Implemented Interfaces:
NamespaceResolver, Receiver, Result

public class NamespaceReducer
extends ProxyReceiver
implements NamespaceResolver

NamespaceReducer is a ProxyReceiver responsible for removing duplicate namespace declarations. It also ensures that an xmlns="" undeclaration is output when necessary. Used on its own, the NamespaceReducer simply eliminates unwanted namespace declarations. It can also be subclassed, in which case the subclass can use the services of the NamespaceReducer to resolve QNames.

The NamespaceReducer also validates namespace-sensitive content.

Field Summary

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

nextReceiver

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

pipelineConfiguration, previousAtomic, systemId

Constructor Summary

NamespaceReducer()
Create a NamespaceReducer
NamespaceReducer(Receiver base)
Create a NamespaceReducer with a given destination Receiver

Method Summary

void
endElement()
endElement: Discard the namespaces declared on this element.
protected short
getURICode(short prefixCode)
Get the URI code corresponding to a given prefix code, by searching the in-scope namespaces.
String
getURIForPrefix(String prefix, boolean useDefault)
Get the namespace URI corresponding to a given prefix.
Iterator
iteratePrefixes()
Get an iterator over all the prefixes declared in this namespace context.
void
namespace(int namespaceCode, int properties)
Output a namespace node (binding)
void
startContent()
startContent: Add any namespace undeclarations needed to stop namespaces being inherited from parent elements
void
startElement(int nameCode, int typeCode, int locationId, int properties)
startElement.

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

append, attribute, characters, close, comment, endDocument, endElement, getConfiguration, getDocumentLocator, getNamePool, getUnderlyingReceiver, namespace, open, processingInstruction, setPipelineConfiguration, setSystemId, setUnderlyingReceiver, setUnparsedEntity, startContent, startDocument, startElement

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

append, getConfiguration, getNamePool, getPipelineConfiguration, getSystemId, open, setPipelineConfiguration, setSystemId, setUnparsedEntity

Constructor Details

NamespaceReducer

public NamespaceReducer()
Create a NamespaceReducer

NamespaceReducer

public NamespaceReducer(Receiver base)
Create a NamespaceReducer with a given destination Receiver
Parameters:
base - the Receiver to which events will be passed after namespace reduction

Method Details

endElement

public void endElement()
            throws XPathException
endElement: Discard the namespaces declared on this element.
Specified by:
endElement in interface Receiver
Overrides:
endElement in interface ProxyReceiver

getURICode

protected short getURICode(short prefixCode)
Get the URI code corresponding to a given prefix code, by searching the in-scope namespaces. This is a service provided to subclasses.
Parameters:
prefixCode - the 16-bit prefix code required
Returns:
the 16-bit URI code, or -1 if the prefix is not found

getURIForPrefix

public String getURIForPrefix(String prefix,
                              boolean useDefault)
Get the namespace URI corresponding to a given prefix. Return null if the prefix is not in scope.
Specified by:
getURIForPrefix in interface NamespaceResolver
Parameters:
prefix - the namespace prefix
useDefault - true if the default namespace is to be used when the prefix is ""
Returns:
the uri for the namespace, or null if the prefix is not in scope

iteratePrefixes

public Iterator iteratePrefixes()
Get an iterator over all the prefixes declared in this namespace context. This will include the default namespace (prefix="") and the XML namespace where appropriate
Specified by:
iteratePrefixes in interface NamespaceResolver

namespace

public void namespace(int namespaceCode,
                      int properties)
            throws XPathException
Output a namespace node (binding)
Specified by:
namespace in interface Receiver
Overrides:
namespace in interface ProxyReceiver
Parameters:
namespaceCode - encapsulates the prefix and URI
properties - the properties of the namespace binding
Throws:
XPathException -

startContent

public void startContent()
            throws XPathException
startContent: Add any namespace undeclarations needed to stop namespaces being inherited from parent elements
Specified by:
startContent in interface Receiver
Overrides:
startContent in interface ProxyReceiver

startElement

public void startElement(int nameCode,
                         int typeCode,
                         int locationId,
                         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 interface ProxyReceiver