net.sf.saxon.functions

Class StartsWith

java.lang.Object

net.sf.saxon.expr.Expression

net.sf.saxon.expr.FunctionCall

net.sf.saxon.functions.SystemFunctionCall

net.sf.saxon.functions.CollatingFunction

net.sf.saxon.functions.StartsWith

All Implemented Interfaces:

Serializable, SourceLocator, LocationProvider, SaxonLocator, Callable, InstructionInfo, Locator

public class StartsWith
extends CollatingFunction
implements Callable

Implements the fn:starts-with() function

See Also:

Serialized Form

Field Summary

Fields inherited from class net.sf.saxon.functions.CollatingFunction

staticCollation

Fields inherited from class net.sf.saxon.functions.SystemFunctionCall

operation

Fields inherited from class net.sf.saxon.expr.FunctionCall

argument

Fields inherited from class net.sf.saxon.expr.Expression

EFFECTIVE_BOOLEAN_VALUE, EVALUATE_METHOD, EVENT_FEED_METHOD, INHERITED_CONTEXT, INSPECTION_CONTEXT, ITEM_FEED_METHOD, ITERATE_METHOD, locationId, MAX_SEQUENCE_LENGTH, MAX_STRING_LENGTH, NAVIGATION_CONTEXT, NODE_VALUE_CONTEXT, PROCESS_METHOD, PUSH_SELECTION, staticProperties, UNBOUNDED_LOWER, UNBOUNDED_UPPER, W3C_CONSUMING, W3C_FREE_RANGING, W3C_GROUP_CONSUMING, W3C_MOTIONLESS, WATCH_METHOD

Constructor Summary

Constructors

Constructor and Description
StartsWith()

Method Summary

Methods

Modifier and Type	Method and Description
Sequence	call(XPathContext context, Sequence[] arguments) Call the Callable.
boolean	effectiveBooleanValue(XPathContext context) Get the effective boolean value of the expression.
BooleanValue	evaluateItem(XPathContext context) Evaluate the function
protected int	getCollationArgument() Get the argument position (0-based) containing the collation name
ExpressionCompiler	getExpressionCompiler() Return the compiler of the StartsWith expression
static boolean	startsWith(StringValue arg0, StringValue arg1, StringCollator collator)

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

bindStaticContext, checkArguments, copy, equals, expandCollationURI, getAtomicComparer, getCollator, getCollatorFromLastArgument, getExpressionBaseURI, getPreAllocatedAtomicComparer, getStaticCollation, preAllocateComparer

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

addContextDocumentArgument, addDocToPathMap, computeCardinality, computeSpecialProperties, equalOrNull, getContextNode, getConvertingCallable, getDefaultArgumentNode, getDetails, getErrorCodeForTypeErrors, getFunctionItemType, getImplementationMethod, getItemType, getOperation, getRequiredType, iterateSubExpressionInfo, makeSystemFunction, optimize, setDetails, useContextItemAsDefault

Methods inherited from class net.sf.saxon.expr.FunctionCall

addExternalFunctionCallToPathMap, checkArgumentCount, explain, getArguments, getDisplayName, getExpressionName, getFunctionName, getNumberOfArguments, hashCode, iterateSubExpressions, preEvaluate, promote, replaceSubExpression, setArguments, setFunctionName, simplify, simplifyArguments, toString, typeCheck

Methods inherited from class net.sf.saxon.expr.Expression

addToPathMap, adoptChildExpression, checkForUpdatingSubexpressions, checkPermittedContents, computeDependencies, computeStaticProperties, doPromotion, dynamicError, evaluateAsString, evaluatePendingUpdates, explain, getCardinality, getColumnNumber, getColumnNumber, getConstructType, getContainer, getDependencies, getEvaluationMethod, getExecutable, getHostLanguage, getIntegerBounds, getIntrinsicDependencies, getLineNumber, getLineNumber, getLocationId, getLocationProvider, getObjectName, getProperties, getProperty, getPublicId, getSlotsUsed, getSpecialProperties, getStreamability, getStreamingAdjunct, getSystemId, getSystemId, hasVariableBinding, implementsStaticTypeCheck, isSubtreeExpression, isUpdatingExpression, isVacuousExpression, iterate, iterateEvents, markTailFunctionCalls, process, resetLocalStaticProperties, setContainer, setEvaluationMethod, setFiltered, setFlattened, setLocationId, staticTypeCheck, suppressValidation, toPattern, toStreamingPattern, typeError

Methods inherited from class java.lang.Object

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

Constructor Detail

StartsWith

public StartsWith()

Method Detail

getCollationArgument

protected int getCollationArgument()

Get the argument position (0-based) containing the collation name

Specified by:

getCollationArgument in class CollatingFunction

Returns:

the position of the argument containing the collation URI

effectiveBooleanValue

public boolean effectiveBooleanValue(XPathContext context)
                              throws XPathException

Get the effective boolean value of the expression. This returns false if the value is the empty sequence, a zero-length string, a number equal to zero, or the boolean false. Otherwise it returns true.

Overrides:

effectiveBooleanValue in class Expression

Parameters:

context - The context in which the expression is to be evaluated

Returns:

the effective boolean value

Throws:

XPathException - if any dynamic error occurs evaluating the expression

startsWith

public static boolean startsWith(StringValue arg0,
                 StringValue arg1,
                 StringCollator collator)
                          throws XPathException

Throws:

XPathException

evaluateItem

public BooleanValue evaluateItem(XPathContext context)
                          throws XPathException

Evaluate the function

Overrides:

evaluateItem in class Expression

Parameters:

context - The context in which the expression is to be evaluated

Returns:

the node or atomic value that results from evaluating the expression; or null to indicate that the result is an empty sequence

Throws:

XPathException - if any dynamic error occurs evaluating the expression

call

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

Description copied from interface: Callable

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 methd 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

getExpressionCompiler

public ExpressionCompiler getExpressionCompiler()

Return the compiler of the StartsWith expression

Overrides:

getExpressionCompiler in class Expression

Returns:

the relevant ExpressionCompiler