com.saxonica.extra
Class Projector

java.lang.Object
  net.sf.saxon.event.SequenceReceiver
      net.sf.saxon.event.ProxyReceiver
          com.saxonica.extra.Projector

All Implemented Interfaces:

Result, Receiver

public class Projector
extends ProxyReceiver

This class uses a PathMap to do document projection. It acts as a push filter, passing through only those events that are necessary to evaluate the expression that was used to generate the PathMap.

Field Summary

Fields inherited from interface javax.xml.transform.Result

PI_DISABLE_OUTPUT_ESCAPING, PI_ENABLE_OUTPUT_ESCAPING

Constructor Summary

Projector(PathMap.PathMapRoot pathMapRoot)
Create a document projector

Method Summary

void	attribute(int nameCode, int typeCode, CharSequence value, int locationId, int properties) Notify an attribute.
void	characters(CharSequence chars, int locationId, int properties) Character data
void	comment(CharSequence chars, int locationId, int properties) Output a comment
void	endDocument() Notify the end of a document node
void	endElement() End of element
static void	main(String[] args) Main program for testing
void	namespace(int namespaceCode, int properties) Notify a namespace.
void	outputStatistics(PrintStream out) Output statistics showing the effectiveness of filtering
void	processingInstruction(String target, CharSequence data, int locationId, int properties) Processing Instruction
void	setPipelineConfiguration(PipelineConfiguration pipe) Set the pipeline configuration
void	startElement(int nameCode, int typeCode, int locationId, int properties) Notify the start of an element

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

append, close, getConfiguration, getDocumentLocator, getNamePool, getUnderlyingReceiver, open, setSystemId, setUnderlyingReceiver, setUnparsedEntity, startContent, startDocument

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

getPipelineConfiguration, getSystemId

Methods inherited from class java.lang.Object

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

Constructor Detail

Projector

public Projector(PathMap.PathMapRoot pathMapRoot)

Create a document projector

Parameters:

pathMapRoot - defines the paths within the document that need to be retained

Method Detail

setPipelineConfiguration

public void setPipelineConfiguration(PipelineConfiguration pipe)

Description copied from interface: Receiver

Set the pipeline configuration

Specified by:

setPipelineConfiguration in interface Receiver

Overrides:

setPipelineConfiguration in class ProxyReceiver

Parameters:

pipe - the pipeline configuration

startElement

public void startElement(int nameCode,
                         int typeCode,
                         int locationId,
                         int properties)
                  throws XPathException

Description copied from class: ProxyReceiver

Notify the start of an element

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.

locationId - an integer which can be interpreted using a LocationProvider to return information such as line number and system ID. If no location information is available, the value zero is supplied.

properties - properties of the element node

Throws:

XPathException

attribute

public void attribute(int nameCode,
                      int typeCode,
                      CharSequence value,
                      int locationId,
                      int properties)
               throws XPathException

Description copied from class: ProxyReceiver

Notify an attribute. Attributes are notified after the startElement event, and before any children. Namespaces and attributes may be intermingled.

Specified by:

attribute in interface Receiver

Overrides:

attribute in class ProxyReceiver

Parameters:

nameCode - The name of the attribute, as held in the name pool

typeCode - The type of the attribute, as held in the name pool

value - the string value of the attribute

locationId - an integer which can be interpreted using a LocationProvider to return information such as line number and system ID. If no location information is available, the value zero is supplied.

properties - Bit significant value. The following bits are defined:

DISABLE_ESCAPING

Disable escaping for this attribute

NO_SPECIAL_CHARACTERS

Attribute value contains no special characters

Throws:

XPathException

namespace

public void namespace(int namespaceCode,
                      int properties)
               throws XPathException

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.

properties - The most important property is REJECT_DUPLICATES. If this property is set, the namespace declaration will be rejected if it conflicts with a previous declaration of the same prefix. If the property is not set, the namespace declaration will be ignored if it conflicts with a previous declaration. This reflects the fact that when copying a tree, namespaces for child elements are emitted before the namespaces of their parent element. Unfortunately this conflicts with the XSLT rule for complex content construction, where the recovery action in the event of conflicts is to take the namespace that comes last. XSLT therefore doesn't recover from this error: it sets the REJECT_DUPLICATES flag, and this is treated as a hard error.

Throws:

XPathException

characters

public void characters(CharSequence chars,
                       int locationId,
                       int properties)
                throws XPathException

Description copied from class: ProxyReceiver

Character data

Specified by:

characters in interface Receiver

Overrides:

characters in class ProxyReceiver

Parameters:

chars - The characters

locationId - an integer which can be interpreted using a LocationProvider to return information such as line number and system ID. If no location information is available, the value zero is supplied.

properties - Bit significant value. The following bits are defined:

DISABLE_ESCAPING

Disable escaping for this text node

USE_CDATA

Output as a CDATA section

Throws:

XPathException

comment

public void comment(CharSequence chars,
                    int locationId,
                    int properties)
             throws XPathException

Description copied from class: ProxyReceiver

Output a comment

Specified by:

comment in interface Receiver

Overrides:

comment in class ProxyReceiver

Parameters:

chars - The content of the comment

locationId - an integer which can be interpreted using a LocationProvider to return information such as line number and system ID. If no location information is available, the value zero is supplied.

properties - Additional information about the comment. The following bits are defined:

CHECKED

Comment is known to be legal (e.g. doesn't contain "--")

Throws:

XPathException

processingInstruction

public void processingInstruction(String target,
                                  CharSequence data,
                                  int locationId,
                                  int properties)
                           throws XPathException

Description copied from class: ProxyReceiver

Processing Instruction

Specified by:

processingInstruction in interface Receiver

Overrides:

processingInstruction in class ProxyReceiver

Parameters:

target - The PI name. This must be a legal name (it will not be checked).

data - The data portion of the processing instruction

locationId - an integer which can be interpreted using a LocationProvider to return information such as line number and system ID. If no location information is available, the value zero is supplied.

properties - Additional information about the PI. The following bits are defined:

CHECKED

Data is known to be legal (e.g. doesn't contain "?>")

Throws:

XPathException

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

endDocument

public void endDocument()
                 throws XPathException

Description copied from class: ProxyReceiver

Notify the end of a document node

Specified by:

endDocument in interface Receiver

Overrides:

endDocument in class ProxyReceiver

Throws:

XPathException

outputStatistics

public void outputStatistics(PrintStream out)

Output statistics showing the effectiveness of filtering

Parameters:

out - the output destination

main

public static void main(String[] args)
                 throws Exception

Main program for testing

Parameters:

args -

arg[0]: source file name

arg[1]: either "xpath" or "xquery"

arg[2]: for "xpath" - a path expression. For "xquery": filename of file containing the query

The ,ethod constructs a pathmap for the given path expression or query and then uses it to project the source document, which is then serialized. Note that the query is not evaluated, it is only used to project the source document.

Throws:

Exception