Package org.basex.query.expr

Class Cmp

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.expr.Cmp

Direct Known Subclasses:

CmpG, CmpN, CmpV

public abstract class Cmp
extends Arr

Abstract comparison.

Author:

BaseX Team 2005-21, BSD License, Christian Gruen

Field Summary

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

exprs

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

exprType, info

Method Summary

Modifier and Type	Method	Description
abstract Expr	invert()	If possible, returns an expression with inverted operands.
final Expr	invert(CompileContext cc)	If possible, returns an optimized expression with inverted operands.
final Expr	optPred(Expr root, CompileContext cc)	Optimizes this expression as predicate.
abstract CmpV.OpV	opV()	Returns the value operator of the expression.

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

accept, allAreValues, args, checkUp, compile, copyAll, count, equals, exprSize, flatten, has, inline, inline, inlineable, mayBePositional, plan, 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, value

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

arg, atomItem, atomIter, copy, data, data, ddo, funcType, hasFreeVars, indexAccessible, isSimple, markTailCalls, mergeEbv, optimize, simplifyFor, typeCheck, uses, vacuous, visitAll

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

description, plan, toErrorString, toString

Methods inherited from class java.lang.Object

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

Method Details

invert

public final Expr invert(CompileContext cc)
                  throws QueryException

If possible, returns an optimized expression with inverted operands.

Parameters:

cc - compilation context

Returns:

original or modified expression

Throws:

QueryException - query exception

invert

public abstract Expr invert()

If possible, returns an expression with inverted operands.

Returns:

original or null

opV

public abstract CmpV.OpV opV()

Returns the value operator of the expression.

Returns:

operator, or null for node comparisons

optPred

public final Expr optPred(Expr root,
 CompileContext cc)
                   throws QueryException

Optimizes this expression as predicate.

Parameters:

root - root expression

cc - compilation context

Returns:

resulting expression

Throws:

QueryException - query exception