Package net.sf.saxon.functions

Class Lang

java.lang.Object

net.sf.saxon.functions.AbstractFunction

net.sf.saxon.functions.SystemFunction

net.sf.saxon.functions.Lang

All Implemented Interfaces:

Callable, IContextAccessorFunction, IFunctionWithRetainedParameterNames, FunctionItem, GroundedValue, Item, Sequence

public class Lang
extends SystemFunction
implements IContextAccessorFunction

Constructor Summary

Constructors

Constructor	Description
Lang()

Method Summary

Modifier and Type	Method	Description
FunctionItem	bindContext(XPathContext context)	Bind context information to appear as part of the function's closure.
BooleanValue	call(XPathContext context, Sequence[] arguments)	Evaluate the expression
boolean	dependsOnContext()	Ask whether this function is actually dependent on the dynamic context
static boolean	isLang(String arglang, NodeInfo target)	Test whether the context node has the given language attribute

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

Constructor Details

Lang

public Lang()

Method Details

dependsOnContext

public boolean dependsOnContext()

Description copied from interface: IContextAccessorFunction

Ask whether this function is actually dependent on the dynamic context

Specified by:

dependsOnContext in interface IContextAccessorFunction

Returns:

true if the function cannot be used unless the dynamic context is first bound

isLang

public static boolean isLang(String arglang,
 NodeInfo target)

Test whether the context node has the given language attribute

Parameters:

arglang - the language being tested

target - the target node

Returns:

true if the node is tagged with this language code

call

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

Evaluate the expression

Specified by:

call in interface Callable

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

bindContext

public FunctionItem bindContext(XPathContext context)
                         throws XPathException

Bind context information to appear as part of the function's closure. If this method has been called, the supplied context will be used in preference to the context at the point where the function is actually called.

Specified by:

bindContext in interface IContextAccessorFunction

Parameters:

context - the context to which the function applies. Must not be null.

Throws:

XPathException