Package net.sf.saxon.functions

This package provides implementations of all the core functions available for use in XPath expressions. This includes all the functions defined in the XPath 2.0 Functions and Operators specification, as well as the additional functions defined for use in XSLT. The package also includes Saxon extension functions. Most of these are in a single class Extensions, but some of the more complex functions are in their own classes, for example Evaluate implements saxon:evaluate().

There is one class for group of closely-related functions. These all inherit from the class net.sf.saxon.expr.Function. The class StandardFunction is used to map a function name to its implementation; it contains tables of information describing the signature of each function, so that the type-checking code is completely generic.

The package also contains machinery for defining user extension functions. A collection of functions is represented by a FunctionLibrary object. There are several standard function libraries available, covering core functions, Saxon extension functions constructor functions, and user extension functions: each category is covered by a subclass of FunctionLibrary, and there is also a FunctionLibraryList that represents the total collection of functions in these individual libraries. The JavaExtensionLibrary contains the logic for binding Java extension functions given their name and arity and the types of their arguments. The class ExtensionFunctionCall contains the run-time logic for converting XPath values to the required Java types, and for converting the result back to an XPath value.

These classes, although public, will not normally be used directly by user-written Java applications. There are a few exceptions, such as ResolveURI which deliberately expose functionality equivalent to the XPath function in a static method.

Interface Summary

Interface	Description
Fold
FunctionLibrary	A FunctionLibrary handles the binding of function calls in XPath (or XQuery) expressions.
PushableFunction	Interface implemented by functions that have a "push" implementation, whereby the result of the function is written incrementally to an Outputter rather than being returned as the result of a call() method.
StatefulSystemFunction

Class Summary

Class	Description
Abs	This class implements the fn:abs() function
AbstractFunction	Abstract superclass (and factory class) for implementations of Function
AccessorFn	This class supports the get_X_from_Y functions defined in XPath 2.0
AccessorFn.DayFromDate
AccessorFn.DayFromDateTime
AccessorFn.DaysFromDuration
AccessorFn.HoursFromDateTime
AccessorFn.HoursFromDuration
AccessorFn.HoursFromTime
AccessorFn.LocalNameFromQName
AccessorFn.MinutesFromDateTime
AccessorFn.MinutesFromDuration
AccessorFn.MinutesFromTime
AccessorFn.MonthFromDate
AccessorFn.MonthFromDateTime
AccessorFn.MonthsFromDuration
AccessorFn.NamespaceUriFromQName
AccessorFn.PrefixFromQName
AccessorFn.SecondsFromDateTime
AccessorFn.SecondsFromDuration
AccessorFn.SecondsFromTime
AccessorFn.TimezoneFromDate
AccessorFn.TimezoneFromDateTime
AccessorFn.TimezoneFromTime
AccessorFn.YearFromDate
AccessorFn.YearFromDateTime
AccessorFn.YearsFromDuration
AccumulatorFn	Non-streaming implementation of accumulator-before() and accumulator-after()
AccumulatorFn.AccumulatorAfter
AccumulatorFn.AccumulatorBefore
Adjust_1	This class implements the XPath 2.0 functions adjust-date-to-timezone(), adjust-time-timezone(), and adjust-dateTime-timezone(), with a single argument
Adjust_2	This class implements the XPath 2.0 functions adjust-date-to-timezone(), adjust-time-timezone(), and adjust-dateTime-timezone(), with two arguments
Aggregate	This abstract class provides functionality common to the sum(), avg(), count(), exists(), and empty() functions.
AnalyzeStringFn	Implements the fn:analyze-string function defined in XPath 3.0.
ApplyFn	This class implements the function fn:apply(), which is a standard function in XQuery 3.1.
AvailableEnvironmentVariables
AvailableSystemProperties
Average	Implementation of the fn:avg function
BaseUri_1	This class implements the fn:base-uri() function in XPath 2.0
BooleanFn	This class supports the XPath function boolean()
CallableFunction	A function item that wraps a Callable
Ceiling	This class supports the ceiling() function
CharactersFn	Implements the proposed fn:characters() function.
CodepointEqual	Implements the XPath 2.0 fn:codepoint-equal() function.
CodepointsToString	This class implements the function fn:codepoints-to-string()
CollatingFunctionFixed	Abstract superclass for functions that take an optional collation argument, in which the collation is not present as an explicit argument, either because it was defaulted in the original function call, or because it has been bound during static analysis.
CollatingFunctionFree	Generic class for all functions that take an optional collation argument, where the collation argument is supplied and has not yet been resolved.
CollationKeyFn	Implements the collation-key function defined in the XSLT 3.0 and XPath 3.1 specifications
CollectionFn	Implement the fn:collection() function.
Compare	This class implements the XPath 2.0 fn:compare() function
Concat	Implementation of the fn:concat() function
ConstantFunction	A ConstantFunction is a zero-argument function that always delivers the same result, supplied at the time the function is instantiated.
ConstantFunction.False
ConstantFunction.True
Contains	Implements the fn:contains() function, with the collation already known
ContainsToken	Implements the fn:contains-token() function with the collation already bound.
ContextAccessorFunction	A ContextAccessorFunction is a function that is dependent on the dynamic context.
ContextItemAccessorFunction	A ContextItemAccessorFunction is a function that takes no arguments, but operates implicitly on the context item.
ContextItemAccessorFunction.Number_0	Subclass of ContextItemAccessorFunction to handle number().
ContextItemAccessorFunction.StringAccessor	Subclass of ContextItemAccessorFunction to handle string-length() and normalize-space().
CopyOfFn	XSLT 3.0 function copy-of().
Count	Implementation of the fn:count function
Current	Implement the XSLT current() function
CurrentGroup	Implements the XSLT function current-group()
CurrentGroupCall	Implements the XSLT function current-group()
CurrentGroupingKey	Implements the XSLT function current-grouping-key()
CurrentGroupingKeyCall	Implements the XSLT function current-grouping-key()
CurrentMergeGroup	Implements the XSLT 3.0 function current-merge-group()
CurrentMergeKey	Implements the XSLT function current-grouping-key()
CurrentOutputUri	This class implements the XSLT 3.0 function current-output-uri()
Data_1	Implement XPath function fn:data() with a single argument
DateTimeConstructor	This class supports the dateTime($date, $time) function
DeepEqual	XSLT 2.0 deep-equal() function, where the collation is already known.
DistinctValues	The XPath 2.0 distinct-values() function, with the collation argument already known
DistinctValues.DistinctIterator	Iterator class to return the distinct values in a sequence
Doc	Implement the fn:doc() function - a simplified form of the Document function
Doc_2	Implement the saxon:doc() function - a variant of the fn:doc function with a second argument to supply option parameters.
DocAvailable	Implement the fn:doc-available() function
DocumentFn	Implements the XSLT document() function
DocumentUri_1	This class supports the document-uri() function
DynamicContextAccessor	A DynamicContextAccessor is a function that takes no arguments, but operates implicitly on the dynamic context.
DynamicContextAccessor.CurrentDate
DynamicContextAccessor.CurrentDateTime
DynamicContextAccessor.CurrentTime
DynamicContextAccessor.DefaultLanguage
DynamicContextAccessor.ImplicitTimezone
ElementAvailable	This class supports the XSLT element-available function.
Empty	Implementation of the fn:empty function
EncodeForUri	This class supports the function fn:encode-for-uri()
EndsWith	Implements the fn:ends-with() function, with the collation already fixed
EnvironmentVariable	Implement the XPath 3.0 fn:environment-variable() function
Error	Implement XPath function fn:error()
EscapeHtmlUri	This class supports the function fn:escape-html-uri()
ExecutableFunctionLibrary	An ExecutableFunctionLibrary is a function library that contains definitions of functions for use at run-time.
Exists	Implementation of the fn:exists function
Floor	This class implements the fn:floor() function
FoldingFunction	Implementation of aggregate functions such as sum() and avg() that supply a fold() function.
FormatDate	Implement the format-date(), format-time(), and format-dateTime() functions in XSLT 2.0 and XQuery 1.1.
FormatInteger
FormatNumber	Implementation of format-number() function.
FormatNumber.SubPicture	Inner class to represent one sub-picture (the negative or positive subpicture)
FunctionAvailable	This class implements the XSLT function-available functions.
FunctionLibraryList	A FunctionLibraryList is a list of FunctionLibraries.
GenerateId_1	This class supports the generate-id() function with one argument
HasChildren_1	This class implements the function fn:has-children($node), which is a standard function in XPath 3.0
HeadFn	This class implements the function fn:head(), which is a standard function in XPath 3.0
Idref
IndexOf	The XPath 2.0 index-of() function, with the collation already known
Innermost	This class implements the function fn:has-children(), which is a standard function in XPath 3.0
InScopePrefixes	This class implements the XPath 2.0 function fn:in-scope-prefixes()
InsertBefore	The XPath 2.0 insert-before() function
InsertBefore.InsertIterator	Insertion iterator.
IntegratedFunctionCall	Expression representing a call to a user-written extension function implemented as a subtype of ExtensionFunctionCall
IntegratedFunctionCall.ConfigurationCheckingFunction	This class checks that NodeInfo objects returned by an extension function were created under the right Configuration
IntegratedFunctionLibrary	A library of integrated function calls, that is, user-written extension functions implemented as instances of the class IntegratedFunction.
IriToUri	This class supports the functions encode-for-uri() and iri-to-uri()
IsIdRef	This class implements the saxon:is-idref() extension function, which is specially-recognized by the system because calls are generated by the optimizer.
KeyFn
Lang
LocalName_1	This class supports the local-name() function
LowerCase	This class implements the fn:lower-case() function
Matches	This class implements the 3-argument matches() function for regular expression matching
MathFunctionSet	Abstract class providing functionality common to functions math:sin(), math:cos(), math:sqrt() etc; contains the concrete implementations of these functions as inner subclasses
MathFunctionSet.AcosFn	Implement math:acos
MathFunctionSet.AsinFn	Implement math:asin
MathFunctionSet.Atan2Fn	Implement math:atan2
MathFunctionSet.AtanFn	Implement math:atan
MathFunctionSet.CosFn	Implement math:cos
MathFunctionSet.Exp10Fn	Implement math:exp10
MathFunctionSet.ExpFn	Implement math:exp
MathFunctionSet.Log10Fn	Implement math:log10
MathFunctionSet.LogFn	Implement math:log
MathFunctionSet.PiFn	Implement math:pi
MathFunctionSet.PowFn	Implement math:pow
MathFunctionSet.SinFn	Implement math:sin
MathFunctionSet.SqrtFn	Implement math:sqrt
MathFunctionSet.TanFn	Implement math:tan
MathFunctionSet.TrigFn1	Generic superclass for all the arity-1 trig functions
Minimax	This class implements the min() and max() functions, with the collation argument already known.
Minimax.Max	Concrete subclass to define the fn:max() function
Minimax.Min	Concrete subclass to define the fn:min() function
Name_1	This class supports the name() function with one argument
NamespaceForPrefix	This class supports the function namespace-uri-for-prefix()
NamespaceUri_1	This class supports the namespace-uri() function
Nilled_1	This class supports the nilled() function
NodeName_1	This class supports the node-name() function with a single argument
NormalizeSpace_1	Implement the XPath normalize-space() function
NormalizeUnicode	Implement the XPath normalize-unicode() function (both the 1-argument and 2-argument versions)
NotFn	This class supports the XPath functions boolean(), not(), true(), and false()
Number_1	Implements the XPath fn:number() function when called with one argument.
OptionsParameter	This class implements the rules for options parameters, as used in functions such as parse-json, serialize, json-to-XML, map:merge.
Outermost	This class implements the function fn:outermost(), which is a standard function in XPath 3.0
ParcelFn	This class implements the function fn:parcel(), which is a proposed function in XPath 4.0 to wrap a sequence as a single item
ParseIetfDate	This class implements the function parse-ietf-date(), which is a standard function in XPath 3.1
ParseXml
ParseXml.RetentiveErrorHandler
ParseXmlFragment
Parts	Proposed XPath 4.0 function that returns the components of an atomic value as a map (for example, the components of a dateTime, a duration, or a URI).
Path_1	Implement the fn:path function with one argument
PositionAndLast
PositionAndLast.Last
PositionAndLast.Position
Put	Implements the fn:put() function in XQuery Update 1.0.
QNameFn	This class supports the fn:QName() function (previously named fn:expanded-QName())
RegexFunction	This class implements any of the functions matches(), replace(), tokenize(), analyze-string(), in the version where a flags argument is present in the argument list
RegexFunctionSansFlags	This class implements any of the functions matches(), replace(), tokenize(), analyze-string(), in which the final "flags" argument is omitted.
RegexGroup
Remove	The XPath 2.0 remove() function
Remove.RemoveIterator	An implementation of SequenceIterator that returns all items except the one at a specified position.
Replace	This class implements the replace() function for replacing substrings that match a regular expression
ResolveQName	This class supports the resolve-QName function in XPath 2.0
ResolveURI	This class supports the resolve-uri() function in XPath 2.0
Reverse	Implement XPath function fn:reverse()
Reverse.ReverseListIterator
Root_1	Implement the XPath 2.0 root() function with one argument
Round	This class implements the fn:round() function
RoundHalfToEven	This class supports the round-to-half-even() function
ScalarSystemFunction	A Scalar system function is a pure function that accepts a single item as its operand, returns a single atomic value as its result, typically returns an empty sequence if the argument is an empty sequence, and has no context dependencies.
Serialize	Implementation of fn:serialize() as defined in XPath 3.1
SnapshotFn	XSLT 3.0 function snapshot().
Sort_1	This class implements the function fn:sort#1, which is a standard function in XPath 3.1
Sort_1.ItemToBeSorted
Sort_2	This class implements the function fn:sort#2, according to the new XPath 3.1 spec in bug 29792
StartsWith	Implements the fn:starts-with() function, with the collation already known
StaticBaseUri	Implement the XPath function static-base-uri()
StaticContextAccessor	A StaticContextAccessor is a function that takes no arguments, but operates implicitly on the static context.
StaticContextAccessor.DefaultCollation	Implement the XPath function default-collation()
StreamAvailable	This class implements the XSLT 3.0 function stream-available()
String_1	Implement XPath function string() with a single argument
StringJoin	fn:string-join(string* $sequence, string $separator)
StringLength_1	Implement the XPath string-length() function
StringToCodepoints	This class supports the function string-to-codepoints()
Subsequence_2	Implements the XPath 2.0 subsequence() function with two arguments
Subsequence_3	Implements the XPath 2.0 subsequence() function with three arguments
Substring	This class implements the XPath substring() function
SubstringAfter	Implements the fn:substring-after() function with the collation already known
SubstringBefore	Implements the fn:substring-before() function with the collation already known
Sum	Implementation of the fn:sum function
SuperId	The XPath id() or element-with-id() function XPath 2.0 version: accepts any sequence as the first parameter; each item in the sequence is taken as an IDREFS value, that is, a space-separated list of ID values.
SuperId.ElementWithId
SuperId.Id
SystemFunction	Abstract superclass for calls to functions in the standard function library
SystemProperty	Implementation of the XSLT system-property() function
TailFn	This class implements the function fn:tail(), which is a standard function in XPath 3.0
Tokenize_1	This class implements the single-argument tokenize() function introduced in XPath 3.1
Tokenize_3	This class implements the 3-argument tokenize() function for regular expression matching.
Trace	This class supports the XPath 2.0 function trace().
TransformFn	This class implements the function transform(), which is a standard function in XPath 3.1
Translate	Implement the XPath translate() function
TreatFn	This class supports the XPath 2.0 functions exactly-one(), one-or-more(), zero-or-one().
TreatFn.ExactlyOne
TreatFn.OneOrMore
TreatFn.ZeroOrOne
TypeAvailable	This class supports the XSLT fn:type-available() function.
Unordered	XPath 2.0 unordered() function
UnparcelFn	This class implements the function fn:unparcel(), which is a proposed function in XPath 4.0 to unwrap a sequence that has been wrapped as a parcel item
UnparsedEntity	Implements the unparsed-entity-uri() function defined in XSLT 1.0 and the unparsed-entity-public-id() function defined in XSLT 2.0
UnparsedEntity.UnparsedEntityPublicId
UnparsedEntity.UnparsedEntityUri
UnparsedText	Implementation of fn:unparsed-text() - with one argument or two
UnparsedTextAvailable
UnparsedTextFunction	Abstract superclass containing common code supporting the functions unparsed-text(), unparsed-text-lines(), and unparsed-text-available()
UnparsedTextLines
UpperCase	This class implements the fn:upper-case() function
UriCollection	Implement the fn:uri-collection() function (new in XQuery 3.0/XSLT 3.0).
URIQueryParameters	A set of query parameters on a URI passed to the collection() or document() function
URIQueryParameters.RegexFilter	A FilenameFilter that tests file names against a regular expression

Enum Summary

Enum	Description
AccessorFn.Component
AccumulatorFn.Phase

Exception Summary

Exception	Description
Error.UserDefinedXPathException