Package org.basex.query.func.fn

Class FnData

java.lang.Object

org.basex.query.expr.ExprInfo

org.basex.query.expr.Expr

org.basex.query.expr.ParseExpr

org.basex.query.expr.Arr

org.basex.query.func.StandardFunc

org.basex.query.func.fn.ContextFn

org.basex.query.func.fn.FnData

public final class FnData
extends ContextFn

Function implementation.

Author:

BaseX Team 2005-21, BSD License, Christian Gruen

Field Summary

Fields inherited from class org.basex.query.func.StandardFunc

definition, sc

Fields inherited from class org.basex.query.expr.Arr

exprs

Fields inherited from class org.basex.query.expr.ParseExpr

exprType, info

Constructor Summary

Constructors

Constructor	Description
FnData()

Method Summary

Modifier and Type	Method	Description
boolean	inlineable()	Indicates if the function will evaluate the current context.
Item	item(QueryContext qc, InputInfo ii)	Evaluates the expression and returns the resulting item, or Empty.VALUE if the expression yields an empty sequence.
Iter	iter(QueryContext qc)	Evaluates the expression and returns an iterator on the resulting items.
protected Expr	opt(CompileContext cc)	Performs function specific optimizations.
protected void	simplifyArgs(CompileContext cc)	Simplifies the types of all arguments.
Expr	simplifyFor(CompileContext.Simplify mode, CompileContext cc)	This function is called at compile time for expressions whose operands might be simplified.
Value	value(QueryContext qc)	Evaluates the expression and returns the resulting value.

Methods inherited from class org.basex.query.func.fn.ContextFn

accept, contextAccess, contextArg, count, ctxArg, has, inline, simplifyEbv

Methods inherited from class org.basex.query.func.StandardFunc

checkAdmin, checkArity, checkArity, checkCreate, checkData, checkPath, checkPath, coerceFunc, compileData, copy, data, data, dataLock, dateTimeToMs, description, equals, optFirst, optFirst, optimize, plan, plan, serialize, toBaseUri, toBindings, toCollation, toDate, toDBNode, toEncodingOrNull, toNodeOrAtomItem, toOptions, toPath, toPath, toQuery, toQuery, vacuous

Methods inherited from class org.basex.query.expr.Arr

allAreValues, args, checkUp, compile, copyAll, exprSize, flatten, inline, inlineable, mayBePositional, simplifyAll

Methods inherited from class org.basex.query.expr.ParseExpr

adoptType, atomValue, checkAllUp, checkNoEmpty, checkNoEmpty, checkNoneUp, checkNoUp, checkType, checkType, checkUp, copyType, ctxValue, ebv, refineType, seqType, size, test, toArray, toArray, toAtomItem, toB64, toB64, toBin, toBin, toBoolean, toBoolean, toBytes, toBytes, toDouble, toDouble, toElem, toFloat, toFunc, toItem, toItem, toLong, toLong, toMap, toMap, toNode, toNode, toNodeOrNull, toNumber, toNumberOrNull, toQNm, toQNm, toToken, toToken, toTokenOrNull, toZeroToken

Methods inherited from class org.basex.query.expr.Expr

arg, atomItem, atomIter, ddo, funcType, hasFreeVars, indexAccessible, isSimple, markTailCalls, mergeEbv, typeCheck, uses, visitAll

Methods inherited from class org.basex.query.expr.ExprInfo

toErrorString, toString

Methods inherited from class java.lang.Object

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

Constructor Details

FnData

public FnData()

Method Details

iter

public Iter iter(QueryContext qc)
          throws QueryException

Description copied from class: Expr

Evaluates the expression and returns an iterator on the resulting items. The implementation of this method is optional.

Overrides:

iter in class ParseExpr

Parameters:

qc - query context

Returns:

iterator

Throws:

QueryException - query exception

value

public Value value(QueryContext qc)
            throws QueryException

Description copied from class: Expr

Evaluates the expression and returns the resulting value. If this method is not implemented, Expr.item(QueryContext, InputInfo) must be implemented instead.

Overrides:

value in class ParseExpr

Parameters:

qc - query context

Returns:

value

Throws:

QueryException - query exception

item

public Item item(QueryContext qc,
 InputInfo ii)
          throws QueryException

Description copied from class: Expr

Evaluates the expression and returns the resulting item, or Empty.VALUE if the expression yields an empty sequence. If this method is not implemented, Expr.value(QueryContext) must be implemented instead.

Overrides:

item in class ParseExpr

Parameters:

qc - query context

ii - input info (only required by Seq instances, which have no input info)

Returns:

item or Empty.VALUE

Throws:

QueryException - query exception

opt

protected Expr opt(CompileContext cc)

Description copied from class: StandardFunc

Performs function specific optimizations.

Overrides:

opt in class StandardFunc

Parameters:

cc - compilation context

Returns:

optimized or original expression

simplifyArgs

protected void simplifyArgs(CompileContext cc)
                     throws QueryException

Description copied from class: StandardFunc

Simplifies the types of all arguments. This function is overwritten by functions that rely on the original argument type.

Overrides:

simplifyArgs in class StandardFunc

Parameters:

cc - compilation context

Throws:

QueryException - query exception

simplifyFor

public Expr simplifyFor(CompileContext.Simplify mode,
 CompileContext cc)
                 throws QueryException

Description copied from class: Expr

This function is called at compile time for expressions whose operands might be simplified.

Overrides:

simplifyFor in class Expr

Parameters:

mode - mode of simplification

cc - compilation context

Returns:

simplified or original expression

Throws:

QueryException - query exception

See Also:

• CompileContext.Simplify

inlineable

public boolean inlineable()

Description copied from class: ContextFn

Indicates if the function will evaluate the current context.

Overrides:

inlineable in class ContextFn

Returns:

result of check