public class BooleanFn extends SystemFunction
Modifier and Type | Field and Description |
---|---|
static int |
BOOLEAN |
static int |
FALSE |
static int |
NOT |
static int |
TRUE |
operation
argument
locationId, staticProperties
EVALUATE_METHOD, ITERATE_METHOD, PROCESS_METHOD
Constructor and Description |
---|
BooleanFn() |
Modifier and Type | Method and Description |
---|---|
void |
checkArguments(StaticContext env)
Static analysis: prevent sorting of the argument
|
boolean |
effectiveBooleanValue(XPathContext c)
Evaluate the effective boolean value
|
Item |
evaluateItem(XPathContext context)
Evaluate the function
|
Expression |
optimize(Optimizer opt,
StaticContext env,
ItemType contextItemType)
Perform optimisation of an expression and its subexpressions.
|
Expression |
simplify(StaticContext env)
Simplify the function call.
|
addContextDocumentArgument, computeCardinality, computeSpecialProperties, display, getDetails, getErrorCodeForTypeErrors, getItemType, getRequiredType, main, makeSystemFunction, setDetails, useContextItemAsDefault
checkArgumentCount, getArguments, getDisplayName, getFunctionNameCode, getNumberOfArguments, iterateSubExpressions, preEvaluate, promote, replaceSubExpression, setArguments, setFunctionNameCode, simplifyArguments, typeCheck
adoptChildExpression, checkPermittedContents, computeDependencies, computeStaticProperties, doPromotion, dynamicError, evaluateAsString, getCardinality, getColumnNumber, getConstructType, getDependencies, getExecutable, getHostLanguage, getImplementationMethod, getInstructionInfo, getIntrinsicDependencies, getLineNumber, getLocationId, getLocationProvider, getParentExpression, getPublicId, getSlotsUsed, getSpecialProperties, getSystemId, hasBadParentPointer, iterate, markTailFunctionCalls, process, resetStaticProperties, setLocationId, setParentExpression, setParentExpression, suppressValidation, typeError
public static final int BOOLEAN
public static final int NOT
public static final int TRUE
public static final int FALSE
public Expression simplify(StaticContext env) throws XPathException
simplify
in interface Expression
simplify
in class FunctionCall
env
- the static contextXPathException
- if an error is discovered during expression
rewritingpublic void checkArguments(StaticContext env) throws XPathException
checkArguments
in class SystemFunction
XPathException
public Expression optimize(Optimizer opt, StaticContext env, ItemType contextItemType) throws XPathException
This method is called after all references to functions and variables have been resolved to the declaration of the function or variable, and after all type checking has been done.
optimize
in interface Expression
optimize
in class FunctionCall
opt
- the optimizer in use. This provides access to supporting functions; it also allows
different optimization strategies to be used in different circumstances.env
- the static context of the expressioncontextItemType
- the static type of "." at the point where this expression is invoked.
The parameter is set to null if it is known statically that the context item will be undefined.
If the type of the context item is not known statically, the argument is set to
Type.ITEM_TYPE
StaticError
- if an error is discovered during this phase
(typically a type error)XPathException
public Item evaluateItem(XPathContext context) throws XPathException
evaluateItem
in interface Expression
evaluateItem
in class ComputedExpression
context
- The context in which the expression is to be evaluatedXPathException
- if any dynamic error occurs evaluating the
expressionpublic boolean effectiveBooleanValue(XPathContext c) throws XPathException
effectiveBooleanValue
in interface Expression
effectiveBooleanValue
in class ComputedExpression
c
- The context in which the expression is to be evaluatedXPathException
- if any dynamic error occurs evaluating the
expression