Package net.sf.saxon.event

Class SignificantItemDetector

java.lang.Object

net.sf.saxon.event.SequenceReceiver

net.sf.saxon.event.ProxyReceiver

net.sf.saxon.event.SignificantItemDetector

All Implemented Interfaces:

Result, Receiver

public class SignificantItemDetector
extends ProxyReceiver

This receiver is inserted into the output pipeline whenever on-empty or on-non-empty is used (XSLT 3.0). It passes all events to the underlying receiver unchanged, but invokes a callback action when the first item is written.

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
SignificantItemDetector(Receiver next, Action trigger)

Method Summary

Modifier and Type	Method	Description
void	append(Item item, Location locationId, int copyNamespaces)	Append an arbitrary item (node or atomic value) to the output
void	attribute(NodeName nameCode, SimpleType typeCode, CharSequence value, Location locationId, int properties)	Notify an attribute.
void	characters(CharSequence chars, Location locationId, int properties)	Character data
void	comment(CharSequence chars, Location locationId, int properties)	Output a comment
void	endDocument()	Notify the end of a document node
void	endElement()	End of element
boolean	isEmpty()	Ask if the sequence that has been written so far is considered empty
static boolean	isSignificant(Item item)
void	namespace(NamespaceBindingSet namespaceBindings, int properties)	Notify a namespace.
void	processingInstruction(String target, CharSequence data, Location locationId, int properties)	Processing Instruction
void	startDocument(int properties)	Start of a document node.
void	startElement(NodeName elemName, SchemaType typeCode, Location location, int properties)	Notify the start of an element

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

close, getNamePool, getNextReceiver, open, setPipelineConfiguration, setSystemId, setUnderlyingReceiver, setUnparsedEntity, startContent, 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

SignificantItemDetector

public SignificantItemDetector(Receiver next,
                               Action trigger)

Method Detail

startDocument

public void startDocument(int properties)
                   throws XPathException

Start of a document node.

Specified by:

startDocument in interface Receiver

Overrides:

startDocument in class ProxyReceiver

Parameters:

properties - bit-significant integer indicating properties of the document node. The definitions of the bits are in class ReceiverOptions

Throws:

XPathException - if an error occurs

startElement

public void startElement(NodeName elemName,
                         SchemaType typeCode,
                         Location location,
                         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:

elemName - integer code identifying the name of the element within the name pool.

typeCode - the element's type annotation.

location - a location associated with the event (typically either a location in the source document or the stylesheet)

properties - properties of the element node

Throws:

XPathException - if an error occurs

namespace

public void namespace(NamespaceBindingSet namespaceBindings,
                      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:

namespaceBindings - the prefix/uri pair representing the namespace binding

properties - any special properties to be passed on this call

Throws:

XPathException - if an error occurs

attribute

public void attribute(NodeName nameCode,
                      SimpleType typeCode,
                      CharSequence value,
                      Location 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

typeCode - The type of the attribute

value - the string value of the attribute

locationId - The location of the node

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 - if an error occurs

characters

public void characters(CharSequence chars,
                       Location 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 - provides information such as line number and system ID.

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 - if an error occurs

processingInstruction

public void processingInstruction(String target,
                                  CharSequence data,
                                  Location 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 - provides information such as line number and system ID.

properties - Additional information about the PI.

Throws:

XPathException - if an error occurs

comment

public void comment(CharSequence chars,
                    Location 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 - provides information such as line number and system ID.

properties - Additional information about the comment.

Throws:

XPathException - if an error occurs

isSignificant

public static boolean isSignificant(Item item)

append

public void append(Item item,
                   Location locationId,
                   int copyNamespaces)
            throws XPathException

Description copied from class: ProxyReceiver

Append an arbitrary item (node or atomic value) to the output

Specified by:

append in interface Receiver

Overrides:

append in class ProxyReceiver

Parameters:

item - the item to be appended

locationId - the location of the calling instruction, for diagnostics

copyNamespaces - if the item is an element node, this indicates whether its namespaces need to be copied. Values are ReceiverOptions.ALL_NAMESPACES, ReceiverOptions.LOCAL_NAMESPACES; the default (0) means no namespaces

Throws:

XPathException

endDocument

public void endDocument()
                 throws XPathException

Notify the end of a document node

Specified by:

endDocument in interface Receiver

Overrides:

endDocument in class ProxyReceiver

Throws:

XPathException - if an error occurs

endElement

public void endElement()
                throws XPathException

End of element

Specified by:

endElement in interface Receiver

Overrides:

endElement in class ProxyReceiver

Throws:

XPathException - if an error occurs

isEmpty

public boolean isEmpty()

Ask if the sequence that has been written so far is considered empty

Returns:

true if no significant items have been written (or started)