com.saxonica.extra
Class Projector

java.lang.Object
  extended by net.sf.saxon.event.SequenceReceiver
      extended by net.sf.saxon.event.ProxyReceiver
          extended by 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


Copyright (C) Michael H. Kay. All rights reserved.