Package net.sf.saxon.functions

Class SortBy

java.lang.Object

net.sf.saxon.functions.AbstractFunction

net.sf.saxon.functions.SystemFunction

net.sf.saxon.functions.SortBy

All Implemented Interfaces:

Callable, IFunctionWithRetainedParameterNames, FunctionItem, GroundedValue, Item, Sequence

public class SortBy
extends SystemFunction

This class implements the function fn:sort-by, which is a proposed function in XPath 4.0. It also provides supporting code underpinning the implementation of fn:sort.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	SortBy.ItemToBeSorted

Field Summary

Fields

Modifier and Type	Field	Description
static Callable	DATA_FN
static final FunctionItemType	keyFunctionType
static RecordType	sortKeyRecord

Constructor Summary

Constructors

Constructor	Description
SortBy()

Method Summary

Modifier and Type	Method	Description
Sequence	call(XPathContext context, Sequence[] arguments)	Evaluate the expression
static <T> List<T>	listOfOne(T element)
static GroundedValue	sort(SequenceIterator iterator, List<Callable> keyFunctions, List<AtomicComparer> comparers, XPathContext context)	Sort a sequence

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

dependsOnContextItem, dynamicCall, equals, export, exportAdditionalArguments, exportAttributes, fixArguments, getArity, getCardinality, getContextNode, getDescription, getDetails, getElaborator, getErrorCodeForTypeErrors, getFunctionItemType, getFunctionName, getNetCost, getOperandRoles, getParameterNames, getRequiredType, getResultItemType, getResultItemType, getRetainedStaticContext, getSpecialProperties, getStaticBaseUriString, getStreamerName, getUniqueIdentifier, getUniStringArg, hashCode, importAttributes, isSequenceVariadic, isTrustedResultType, makeCall, makeFunction, makeFunction40, makeFunctionCall, makeOptimizedFunctionCall, makeTrueFunctionCall, resultIfEmpty, setArity, setDetails, setRetainedStaticContext, supplyTypeInformation, toShortString, toString, typeCheckCaller

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

atomize, deepEqual40, deepEquals, effectiveBooleanValue, getAnnotations, getUnicodeStringValue, isArray, isMap, makeNewContext, simplify, typeCheck

Methods inherited from class java.lang.Object

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

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

getGenre

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

asIterable, concatenate, containsNode, materialize

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

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

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

makeRepeatable

Field Details

keyFunctionType

public static final FunctionItemType keyFunctionType

sortKeyRecord

public static RecordType sortKeyRecord

DATA_FN

public static Callable DATA_FN

Constructor Details

SortBy

public SortBy()

Method Details

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 SequenceIterators

Returns:

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

Throws:

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

sort

public static GroundedValue sort(SequenceIterator iterator,
 List<Callable> keyFunctions,
 List<AtomicComparer> comparers,
 XPathContext context)
                          throws XPathException

Sort a sequence

Parameters:

iterator - iterator over the input sequence

keyFunctions - list of functions for computing sort key values, major to minor

comparers - list of comparers for comparing sort key values, major to minor

context - XPath dynamic evaluation context

Returns:

the sorted sequence

Throws:

XPathException - for example if there are incomparable keys present

listOfOne

public static <T> List<T> listOfOne(T element)