Package org.basex.query.func.map

Class MapKeys

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.map.MapKeys

public final class MapKeys
extends StandardFunc

Function implementation.

Author:

BaseX Team 2005-21, BSD License, Leo Woerteler

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
MapKeys()

Method Summary

Modifier and Type	Method	Description
protected Expr	opt(CompileContext cc)	Performs function specific optimizations.
Value	value(QueryContext qc)	Evaluates the expression and returns the resulting value.

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, has, optFirst, optFirst, optimize, plan, plan, serialize, simplifyArgs, toBaseUri, toBindings, toCollation, toDate, toDBNode, toEncodingOrNull, toNodeOrAtomItem, toOptions, toPath, toPath, toQuery, toQuery, vacuous

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

accept, allAreValues, args, checkUp, compile, copyAll, count, exprSize, flatten, inline, 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, item, iter, 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, simplifyFor, 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

MapKeys

public MapKeys()

Method Details

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

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