Package net.sf.saxon.functions

Class SnapshotFn

java.lang.Object

net.sf.saxon.functions.AbstractFunction

net.sf.saxon.functions.SystemFunction

net.sf.saxon.functions.SnapshotFn

All Implemented Interfaces:

Callable, Function, GroundedValue, Item, Sequence

public class SnapshotFn
extends SystemFunction

XSLT 3.0 function snapshot(). This is like a deep-copy except that it also includes a shallow copy of all ancestors.

Constructor Summary

Constructors

Constructor	Description
SnapshotFn()

Method Summary

Modifier and Type	Method	Description
Sequence	call(XPathContext context, Sequence[] arguments)	Evaluate the expression
static void	closeAncestors(java.util.List<NodeInfo> ancestors, Receiver bm)
int	getCardinality(Expression[] arguments)	Get the cardinality, given knowledge of the actual arguments
static ItemMappingFunction	getMappingFunction()	Get a mapping function that can be used to take a snapshot of every item in a sequence
java.lang.String	getStreamerName()	Get a name that identifies the class that can be used to evaluate this function in streaming mode, that is, supplying one item or event at a time as it is delivered by the parser.
static java.util.List<NodeInfo>	makeAncestorList(NodeInfo origin)
static BuilderMonitor	openAncestors(NodeInfo origin, java.util.List<NodeInfo> ancestors, XPathContext context)
static SequenceIterator	snapshotSequence(SequenceIterator nodes, XPathContext context)
static Item	snapshotSingle(Item origin)	Take a snapshot of a single item

Methods inherited from class net.sf.saxon.functions.SystemFunction

dependsOnContextItem, dynamicCall, equals, export, exportAdditionalArguments, exportAttributes, fixArguments, getArity, getCompilerName, getContextNode, getDescription, getDetails, getErrorCodeForTypeErrors, getFunctionItemType, getFunctionName, getIntegerBounds, getNetCost, getOperandRoles, getRequiredType, getResultItemType, getResultItemType, getRetainedStaticContext, getSpecialProperties, getStaticBaseUriString, importAttributes, isTrustedResultType, makeCall, makeFunction, makeFunctionCall, makeOptimizedFunctionCall, resultIfEmpty, setArity, setDetails, setRetainedStaticContext, supplyTypeInformation, toShortString, toString, typeCheckCaller

Methods inherited from class net.sf.saxon.functions.AbstractFunction

atomize, deepEquals, effectiveBooleanValue, getAnnotations, getStringValue, getStringValueCS, isArray, isMap, makeNewContext, simplify, typeCheck

Methods inherited from class java.lang.Object

clone, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Methods inherited from interface net.sf.saxon.om.Function

getGenre

Methods inherited from interface net.sf.saxon.om.GroundedValue

asIterable, concatenate, containsNode, materialize

Methods inherited from interface net.sf.saxon.om.Item

getLength, head, isStreamed, itemAt, iterate, reduce, subsequence

Methods inherited from interface net.sf.saxon.om.Sequence

makeRepeatable

Constructor Detail

SnapshotFn

public SnapshotFn()

Method Detail

getCardinality

public int getCardinality(Expression[] arguments)

Description copied from class: SystemFunction

Get the cardinality, given knowledge of the actual arguments

Overrides:

getCardinality in class SystemFunction

Parameters:

arguments - the actual arguments supplied

Returns:

the most precise available cardinality that the function will return

call

public Sequence call(XPathContext context,
                     Sequence[] arguments)
              throws XPathException

Evaluate the expression

Parameters:

context - the dynamic evaluation context

arguments - the values of the arguments, supplied as Sequences

Returns:

the result of the evaluation, in the form of a Sequence

Throws:

XPathException - if a dynamic error occurs during the evaluation of the expression

snapshotSequence

public static SequenceIterator snapshotSequence(SequenceIterator nodes,
                                                XPathContext context)

getMappingFunction

public static ItemMappingFunction getMappingFunction()

Get a mapping function that can be used to take a snapshot of every item in a sequence

Returns:

a suitable mapping function

snapshotSingle

public static Item snapshotSingle(Item origin)

Take a snapshot of a single item

Parameters:

origin - the item in question

Returns:

the snapshot

makeAncestorList

public static java.util.List<NodeInfo> makeAncestorList(NodeInfo origin)

openAncestors

public static BuilderMonitor openAncestors(NodeInfo origin,
                                           java.util.List<NodeInfo> ancestors,
                                           XPathContext context)
                                    throws XPathException

Throws:

XPathException

closeAncestors

public static void closeAncestors(java.util.List<NodeInfo> ancestors,
                                  Receiver bm)
                           throws XPathException

Throws:

XPathException

getStreamerName

public java.lang.String getStreamerName()

Description copied from class: SystemFunction

Get a name that identifies the class that can be used to evaluate this function in streaming mode, that is, supplying one item or event at a time as it is delivered by the parser. Special streaming support is generally available in Saxon-EE for all system functions that take a sequence as their argument.

Overrides:

getStreamerName in class SystemFunction

Returns:

a name that identifies a class that supports streamed evaluation of this system function, or null if no such class is available. The mapping of names to classes is defined in the Saxon-EE class StreamerMap. In non-streaming Saxon editions (HE and PE) the method always returns null.