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 2005-10, ISC License, Christian Gruen

Nested Class Summary

Nested classes/interfaces inherited from class org.basex.query.expr.Expr

Expr.Use

Field Summary

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

expr

Constructor Summary

FTWords(Data d, byte[] t, boolean f)
Index constructor.

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

Method Summary

FTItem	atomic(QueryContext ctx) This method is called by the sequential full-text evaluation.
FTExpr	comp(QueryContext ctx) Optimizes and compiles the expression.
boolean	indexAccessible(IndexContext ic) Checks if an index can be used for query evaluation.
FTExpr	indexEquivalent(IndexContext ic) Returns an equivalent expression which accesses an index structure.
FTIter	iter(QueryContext ctx) This method is called by the index-based full-text evaluation.
void	plan(Serializer ser) Recursively sends the abstract syntax of this expression to the specified serializer.
boolean	removable(Var v, QueryContext ctx) Checks if the specified variable is removable.
FTExpr	remove(Var v) Removes the specified variable in a sub expression.
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, returned, uses

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

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

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)

Sequential constructor.

Parameters:

e - expression

m - search mode

o - occurrences

FTWords

public FTWords(Data d,
               byte[] t,
               boolean f)

Index constructor.

Parameters:

d - data reference

t - text

f - fast evaluation

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 - query exception

atomic

public FTItem atomic(QueryContext ctx)
              throws QueryException

Description copied from class: FTExpr

This method is called by the sequential full-text evaluation.

Specified by:

atomic in class FTExpr

Parameters:

ctx - query context

Returns:

resulting item

Throws:

QueryException - query exception

iter

public FTIter iter(QueryContext ctx)

Description copied from class: FTExpr

This method is called by the index-based full-text evaluation.

Specified by:

iter in class FTExpr

Parameters:

ctx - query context

Returns:

resulting item

indexAccessible

public boolean indexAccessible(IndexContext ic)

Description copied from class: Expr

Checks if an index can be used for query evaluation.

Overrides:

indexAccessible in class Expr

Parameters:

ic - index context

Returns:

true if an index can be used

indexEquivalent

public FTExpr indexEquivalent(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.IndexContext) is implemented for an expression.

Overrides:

indexEquivalent in class FTExpr

Parameters:

ic - index context

Returns:

Equivalent index-expression or null

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

removable

public boolean removable(Var v,
                         QueryContext ctx)

Description copied from class: Expr

Checks if the specified variable is removable.

Overrides:

removable in class FTExpr

Parameters:

v - variable to be removed

ctx - query context

Returns:

result of check

remove

public FTExpr remove(Var v)

Description copied from class: Expr

Removes the specified variable in a sub expression.

Overrides:

remove in class FTExpr

Parameters:

v - variable to be removed

Returns:

expression with removed variable

plan

public void plan(Serializer ser)
          throws 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:

IOException - I/O exception

toString

public String toString()

Specified by:

toString in class ExprInfo