Package com.saxonica.functions.qt4.pin

Class LabeledFunctionItem

java.lang.Object

com.saxonica.functions.qt4.pin.LabeledFunctionItem

All Implemented Interfaces:

LabeledItem, Callable, FunctionItem, GroundedValue, Item, Sequence

public class LabeledFunctionItem
extends Object
implements FunctionItem, LabeledItem

n A LabeledMapItem represents an XDM map together with a label, which is a map: the map typically contains retained information about how the map was selected within a JSON-like tree.

Constructor Summary

Constructors

Constructor	Description
LabeledFunctionItem(FunctionItem subject, MapItem label)	Create a LabeledFunctionItem with a supplied label

Method Summary

Modifier and Type	Method	Description
AtomicSequence	atomize()	Atomize the item.
Sequence	call(XPathContext context, Sequence[] arguments)	Call the Callable.
boolean	deepEqual40(FunctionItem other, XPathContext context, DeepEqual.DeepEqualOptions options)	Test whether this FunctionItem is deep-equal to another function item, under the rules of the deep-equal function in XPath 4.0
boolean	deepEquals(FunctionItem other, XPathContext context, AtomicMatcher comparer, int flags)	Test whether this FunctionItem is deep-equal to another function item, under the rules of the deep-equal function
void	export(ExpressionPresenter out)	Output information about this function item to the diagnostic explain() output
AnnotationList	getAnnotations()	Get the function annotations (as defined in XQuery).
int	getArity()	Get the arity of the function
String	getDescription()	Get a description of this function for use in error messages.
FunctionItemType	getFunctionItemType()	Get the item type of the function item
StructuredQName	getFunctionName()	Get the name of the function, or null if it is anonymous
MapItem	getLabel()	Get the label of this value, typically, information about the containing maps and arrays in the containing tree
OperandRole[]	getOperandRoles()	Get the roles of the arguments, for the purposes of streaming
Item	getSubject()	Get the subject item without its label
UnicodeString	getUnicodeStringValue()	Get the value of the item as a Unicode string.
boolean	isArray()	Ask whether this function item is an array
boolean	isMap()	Ask whether this function item is a map
boolean	isTrustedResultType()	Ask if the function can be trusted to return a result of the correct type
XPathContext	makeNewContext(XPathContext callingContext, ContextOriginator originator)	Prepare an XPathContext object for evaluating the function

Methods inherited from class java.lang.Object

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

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

getGenre, isSequenceVariadic, toShortString

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

asIterable, concatenate, containsNode, effectiveBooleanValue, materialize

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

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

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

makeRepeatable

Constructor Details

LabeledFunctionItem

public LabeledFunctionItem(FunctionItem subject,
 MapItem label)

Create a LabeledFunctionItem with a supplied label

Parameters:

subject - the subject function item

label - the label

Method Details

getSubject

public Item getSubject()

Get the subject item without its label

Specified by:

getSubject in interface LabeledItem

Returns:

the subject item

getLabel

public MapItem getLabel()

Get the label of this value, typically, information about the containing maps and arrays in the containing tree

Specified by:

getLabel in interface Item

Specified by:

getLabel in interface LabeledItem

Returns:

the associated Pedigree.

call

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

Call the Callable.

Specified by:

call in interface Callable

Parameters:

context - the dynamic evaluation context

arguments - the values of the arguments, supplied as Sequences.

Generally it is advisable, if calling iterate() to process a supplied sequence, to call it only once; if the value is required more than once, it should first be converted to a GroundedValue by calling the utility method SequenceTool.toGroundedValue().

If the expected value is a single item, the item should be obtained by calling Sequence.head(): it cannot be assumed that the item will be passed as an instance of Item or AtomicValue.

It is the caller's responsibility to perform any type conversions required to convert arguments to the type expected by the callee. An exception is where this Callable is explicitly an argument-converting wrapper around the original Callable.

Returns:

the result of the evaluation, in the form of a Sequence. It is the responsibility of the callee to ensure that the type of result conforms to the expected result type.

Throws:

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

isMap

public boolean isMap()

Ask whether this function item is a map

Specified by:

isMap in interface FunctionItem

Returns:

true if this function item is a map, otherwise false

isArray

public boolean isArray()

Ask whether this function item is an array

Specified by:

isArray in interface FunctionItem

Returns:

true if this function item is an array, otherwise false

getFunctionItemType

public FunctionItemType getFunctionItemType()

Get the item type of the function item

Specified by:

getFunctionItemType in interface FunctionItem

Returns:

the function item's type

getFunctionName

public StructuredQName getFunctionName()

Get the name of the function, or null if it is anonymous

Specified by:

getFunctionName in interface FunctionItem

Returns:

the function name, or null for an anonymous inline function

getArity

public int getArity()

Get the arity of the function

Specified by:

getArity in interface FunctionItem

Returns:

the number of arguments in the function signature

getOperandRoles

public OperandRole[] getOperandRoles()

Get the roles of the arguments, for the purposes of streaming

Specified by:

getOperandRoles in interface FunctionItem

Returns:

an array of OperandRole objects, one for each argument

getAnnotations

public AnnotationList getAnnotations()

Get the function annotations (as defined in XQuery). Returns an empty list if there are no function annotations.

Specified by:

getAnnotations in interface FunctionItem

Returns:

the function annotations

makeNewContext

public XPathContext makeNewContext(XPathContext callingContext,
 ContextOriginator originator)

Prepare an XPathContext object for evaluating the function

Specified by:

makeNewContext in interface FunctionItem

Parameters:

callingContext - the XPathContext of the function calling expression

originator - identifies the location of the caller for diagnostics

Returns:

a suitable context for evaluating the function (which may or may not be the same as the caller's context)

deepEquals

public boolean deepEquals(FunctionItem other,
 XPathContext context,
 AtomicMatcher comparer,
 int flags)
                   throws XPathException

Test whether this FunctionItem is deep-equal to another function item, under the rules of the deep-equal function

Specified by:

deepEquals in interface FunctionItem

Parameters:

other - the other function item

context - the dynamic evaluation context

comparer - the object to perform the comparison

flags - options for how the comparison is performed

Returns:

true if the two function items are deep-equal

Throws:

XPathException - if the comparison cannot be performed

deepEqual40

public boolean deepEqual40(FunctionItem other,
 XPathContext context,
 DeepEqual.DeepEqualOptions options)
                    throws XPathException

Description copied from interface: FunctionItem

Test whether this FunctionItem is deep-equal to another function item, under the rules of the deep-equal function in XPath 4.0

Specified by:

deepEqual40 in interface FunctionItem

Parameters:

other - the other function item

context - the dynamic evaluation context

options - the options supplied to the deep-equal function

Returns:

true if the two function items are deep-equal

Throws:

XPathException - if the comparison cannot be performed

getDescription

public String getDescription()

Get a description of this function for use in error messages. For named functions, the description is the function name (as a lexical QName). For others, it might be, for example, "inline function", or "partially-applied ends-with function".

Specified by:

getDescription in interface FunctionItem

Returns:

a description of the function for use in error messages

export

public void export(ExpressionPresenter out)
            throws XPathException

Output information about this function item to the diagnostic explain() output

Specified by:

export in interface FunctionItem

Parameters:

out - the destination for the information

Throws:

XPathException - if things go wrong

isTrustedResultType

public boolean isTrustedResultType()

Ask if the function can be trusted to return a result of the correct type

Specified by:

isTrustedResultType in interface FunctionItem

Returns:

true if the implementation can be trusted

getUnicodeStringValue

public UnicodeString getUnicodeStringValue()

Get the value of the item as a Unicode string. For nodes, this is the string value of the node as defined in the XPath 2.0 data model, except that all nodes are treated as being untyped: it is not an error to get the string value of a node with a complex type. For atomic values, the method returns the result of casting the atomic value to a string.

Specified by:

getUnicodeStringValue in interface GroundedValue

Specified by:

getUnicodeStringValue in interface Item

Returns:

the string value of the item

Throws:

UnsupportedOperationException - if the item is a function item (an unchecked exception is used here to avoid introducing exception handling to a large number of paths where it is not needed)

Since:

8.4

atomize

public AtomicSequence atomize()
                       throws XPathException

Atomize the item.

Specified by:

atomize in interface Item

Returns:

the result of atomization

Throws:

XPathException - if atomization is not allowed for this kind of item