org.basex.query.ft
Class FTWords

java.lang.Object
  org.basex.query.ExprInfo
      org.basex.query.expr.Expr
          org.basex.query.ft.FTExpr
              org.basex.query.ft.FTWords

public final class FTWords
extends FTExpr

FTWords expression.

Author:

Workgroup DBIS, University of Konstanz 2005-09, ISC License, Christian Gruen

Field Summary

Fields inherited from class org.basex.query.ft.FTExpr

expr

Constructor Summary

FTWords(Expr e, FTOpt.FTMode m, Expr[] o)
Constructor.

Method Summary

FTExpr	comp(QueryContext ctx) Optimizes and compiles the expression.
void	indexAccessible(QueryContext ctx, IndexContext ic) Checks if an index can be used for query evaluation.
FTExpr	indexEquivalent(QueryContext ctx, IndexContext ic) Returns an equivalent expression which accesses an index structure.
FTNodeIter	iter(QueryContext ctx) Evaluates the expression and returns an iterator on the resulting items.
void	plan(Serializer ser) Recursively sends the abstract syntax of this expression to the specified serializer.
java.lang.String	toString()
boolean	usesExclude() Checks if sub expressions of a mild not operator do not violate the grammar.

Methods inherited from class org.basex.query.ft.FTExpr

color, remove, returned, uses

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

addText, atomic, checkCtx, checkDbl, checkItr, duplicates, e, ebv, i, removable, sameAs, size, test

Methods inherited from class org.basex.query.ExprInfo

info, name

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

FTWords

public FTWords(Expr e,
               FTOpt.FTMode m,
               Expr[] o)

Constructor.

Parameters:

e - expression

m - search mode

o - occurrences

Method Detail

comp

public FTExpr comp(QueryContext ctx)
            throws QueryException

Description copied from class: Expr

Optimizes and compiles the expression.

Overrides:

comp in class FTExpr

Parameters:

ctx - query context

Returns:

optimized Expression

Throws:

QueryException - evaluation exception

iter

public FTNodeIter iter(QueryContext ctx)
                throws QueryException

Description copied from class: Expr

Evaluates the expression and returns an iterator on the resulting items. If this method is not overwritten, Expr.atomic(org.basex.query.QueryContext) must be implemented.

Specified by:

iter in class FTExpr

Parameters:

ctx - query context

Returns:

resulting item

Throws:

QueryException - evaluation exception

indexAccessible

public void indexAccessible(QueryContext ctx,
                            IndexContext ic)

Description copied from class: Expr

Checks if an index can be used for query evaluation.

Overrides:

indexAccessible in class Expr

Parameters:

ctx - query context

ic - index context

indexEquivalent

public FTExpr indexEquivalent(QueryContext ctx,
                              IndexContext ic)

Description copied from class: Expr

Returns an equivalent expression which accesses an index structure. Must be called if Expr.indexAccessible(org.basex.query.QueryContext, org.basex.query.IndexContext) is implemented for an expression.

Overrides:

indexEquivalent in class FTExpr

Parameters:

ctx - query context

ic - index context

Returns:

Equivalent index-expression or null

plan

public void plan(Serializer ser)
          throws java.io.IOException

Description copied from class: ExprInfo

Recursively sends the abstract syntax of this expression to the specified serializer.

Overrides:

plan in class FTExpr

Parameters:

ser - serializer

Throws:

java.io.IOException - exception

toString

public java.lang.String toString()

Specified by:

toString in class ExprInfo

usesExclude

public boolean usesExclude()

Description copied from class: FTExpr

Checks if sub expressions of a mild not operator do not violate the grammar.

Returns:

result of check