Package net.sf.saxon.functions
Class Root
- java.lang.Object
-
- net.sf.saxon.expr.ComputedExpression
-
- net.sf.saxon.expr.FunctionCall
-
- net.sf.saxon.functions.SystemFunction
-
- net.sf.saxon.functions.Root
-
- All Implemented Interfaces:
java.io.Serializable
,javax.xml.transform.SourceLocator
,Container
,Expression
,InstructionInfoProvider
public class Root extends SystemFunction
Implement the XPath 2.0 root() function- See Also:
- Serialized Form
-
-
Field Summary
-
Fields inherited from class net.sf.saxon.functions.SystemFunction
operation
-
Fields inherited from class net.sf.saxon.expr.FunctionCall
argument
-
Fields inherited from class net.sf.saxon.expr.ComputedExpression
locationId, staticProperties
-
Fields inherited from interface net.sf.saxon.expr.Expression
EVALUATE_METHOD, ITERATE_METHOD, PROCESS_METHOD
-
-
Constructor Summary
Constructors Constructor Description Root()
-
Method Summary
All Methods Instance Methods Concrete Methods Modifier and Type Method Description int
computeSpecialProperties()
Get the static properties of this expression (other than its type).Item
evaluateItem(XPathContext c)
Evaluate in a general contextExpression
simplify(StaticContext env)
Simplify and validate.-
Methods inherited from class net.sf.saxon.functions.SystemFunction
addContextDocumentArgument, checkArguments, computeCardinality, display, getDetails, getErrorCodeForTypeErrors, getItemType, getRequiredType, main, makeSystemFunction, setDetails, useContextItemAsDefault
-
Methods inherited from class net.sf.saxon.expr.FunctionCall
checkArgumentCount, getArguments, getDisplayName, getFunctionNameCode, getNumberOfArguments, iterateSubExpressions, optimize, preEvaluate, promote, replaceSubExpression, setArguments, setFunctionNameCode, simplifyArguments, typeCheck
-
Methods inherited from class net.sf.saxon.expr.ComputedExpression
adoptChildExpression, checkPermittedContents, computeDependencies, computeStaticProperties, doPromotion, dynamicError, effectiveBooleanValue, 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
-
-
-
-
Method Detail
-
simplify
public Expression simplify(StaticContext env) throws XPathException
Simplify and validate.- Specified by:
simplify
in interfaceExpression
- Overrides:
simplify
in classFunctionCall
- Parameters:
env
- the static context- Returns:
- the simplified expression
- Throws:
XPathException
- if an error is discovered during expression rewriting
-
computeSpecialProperties
public int computeSpecialProperties()
Get the static properties of this expression (other than its type). The result is bit-significant. These properties are used for optimizations. In general, if property bit is set, it is true, but if it is unset, the value is unknown.- Overrides:
computeSpecialProperties
in classSystemFunction
-
evaluateItem
public Item evaluateItem(XPathContext c) throws XPathException
Evaluate in a general context- Specified by:
evaluateItem
in interfaceExpression
- Overrides:
evaluateItem
in classComputedExpression
- Parameters:
c
- 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
-
-