net.sf.saxon.event
Class NamespaceReducer

java.lang.Object
  |
  +--net.sf.saxon.event.ProxyReceiver
        |
        +--net.sf.saxon.event.NamespaceReducer
All Implemented Interfaces:
Receiver, javax.xml.transform.Result

public class NamespaceReducer
extends ProxyReceiver

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.


Field Summary
 
Fields inherited from class net.sf.saxon.event.ProxyReceiver
baseReceiver, namePool, systemId
 
Fields inherited from interface javax.xml.transform.Result
PI_DISABLE_OUTPUT_ESCAPING, PI_ENABLE_OUTPUT_ESCAPING
 
Constructor Summary
NamespaceReducer()
           
 
Method Summary
 void endElement()
          endElement: Discard the namespaces declared on this element.
protected  int getURICode(short prefixCode)
          Get the URI code corresponding to a given prefix code, by searching the in-scope namespaces.
 void namespace(int namespaceCode, int properties)
          Notify a namespace.
 void setNamePool(NamePool pool)
          Set the name pool to be used for all name codes
 void startContent()
          startContent: Add any namespace undeclarations needed to stop namespaces being inherited from parent elements
 void startElement(int nameCode, int typeCode, int properties)
          startElement.
 
Methods inherited from class net.sf.saxon.event.ProxyReceiver
attribute, characters, comment, endDocument, getNamePool, getSystemId, getUnderlyingReceiver, processingInstruction, setDocumentLocator, setSystemId, setUnderlyingReceiver, setUnparsedEntity, startDocument
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

NamespaceReducer

public NamespaceReducer()
Method Detail

setNamePool

public void setNamePool(NamePool pool)
Set the name pool to be used for all name codes

Specified by:
setNamePool in interface Receiver
Overrides:
setNamePool in class ProxyReceiver

startElement

public void startElement(int nameCode,
                         int typeCode,
                         int properties)
                  throws javax.xml.transform.TransformerException
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:
nameCode - integer code identifying the name of the element within the name pool.
typeCode - integer code identifying the element's type within the name pool.
javax.xml.transform.TransformerException

namespace

public void namespace(int namespaceCode,
                      int properties)
               throws javax.xml.transform.TransformerException
Description copied from class: ProxyReceiver
Notify a namespace. Namespaces are notified after the startElement event, and before any children for the element. The namespaces that are reported are only required to include those that are different from the parent element; however, duplicates may be reported. A namespace must not conflict with any namespaces already used for element or attribute names.

Specified by:
namespace in interface Receiver
Overrides:
namespace in class ProxyReceiver
Parameters:
namespaceCode - an integer: the top half is a prefix code, the bottom half a URI code. These may be translated into an actual prefix and URI using the name pool. A prefix code of zero represents the empty prefix (that is, the default namespace). A URI code of zero represents a URI of "", that is, a namespace undeclaration.
javax.xml.transform.TransformerException

startContent

public void startContent()
                  throws javax.xml.transform.TransformerException
startContent: Add any namespace undeclarations needed to stop namespaces being inherited from parent elements

Specified by:
startContent in interface Receiver
Overrides:
startContent in class ProxyReceiver
javax.xml.transform.TransformerException

endElement

public void endElement()
                throws javax.xml.transform.TransformerException
endElement: Discard the namespaces declared on this element.

Specified by:
endElement in interface Receiver
Overrides:
endElement in class ProxyReceiver
javax.xml.transform.TransformerException

getURICode

protected int 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