Package org.basex.query.expr.path

Class CachedStep

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.Preds

org.basex.query.expr.path.Step

org.basex.query.expr.path.CachedStep

public final class CachedStep
extends Step

Step expression, caching all results.

Author:

BaseX Team 2005-21, BSD License, Christian Gruen

Field Summary

Fields inherited from class org.basex.query.expr.path.Step

axis, test

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
CachedStep(InputInfo info, Axis axis, Test test, Expr... preds)	Constructor.

Method Summary

Modifier and Type	Method	Description
Step	copy(CompileContext cc, IntObjMap<Var> vm)	Copies an expression.
Iter	iter(QueryContext qc)	Evaluates the expression and returns an iterator on the resulting items.

Methods inherited from class org.basex.query.expr.path.Step

accept, equals, exprSize, get, get, get, get, inline, optimize, plan, plan, type, value

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

compile, flattenEbv, inlineable, match, mayBePositional, numeric, simplify

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

allAreValues, args, checkUp, copyAll, count, flatten, has, inline, 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, 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, data, data, ddo, funcType, hasFreeVars, indexAccessible, isSimple, markTailCalls, mergeEbv, simplifyFor, typeCheck, uses, vacuous, visitAll

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

description, toErrorString, toString

Methods inherited from class java.lang.Object

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

Constructor Details

CachedStep

public CachedStep(InputInfo info,
 Axis axis,
 Test test,
 Expr... preds)

Constructor.

Parameters:

info - input info

axis - axis

test - node test

preds - predicates

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

copy

public Step copy(CompileContext cc,
 IntObjMap<Var> vm)

Description copied from class: Expr

Copies an expression. Used for inlining functions, or for copying static queries. It is utilized by VarRef.inline(org.basex.query.InlineContext), FuncItem.inline(org.basex.query.expr.Expr[], org.basex.query.CompileContext), Closure.inline(org.basex.query.InlineContext) and StaticFunc.inline(org.basex.query.expr.Expr[], org.basex.query.CompileContext).

Specified by:

copy in class Step

Parameters:

cc - compilation context

vm - mapping from old variable IDs to new variable copies. Required by Closure.copy(org.basex.query.CompileContext, org.basex.util.hash.IntObjMap<org.basex.query.var.Var>) and VarRef.copy(org.basex.query.CompileContext, org.basex.util.hash.IntObjMap<org.basex.query.var.Var>)

Returns:

copied expression