org.basex.query.expr
Class For

java.lang.Object
  org.basex.query.ExprInfo
      org.basex.query.expr.Expr
          org.basex.query.expr.ForLet
              org.basex.query.expr.For

public final class For
extends ForLet

For Clause.

Author:

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

Constructor Summary

For(Expr e, Var v, Var p, Var s)
Constructor.

Method Summary

Expr	comp(QueryContext ctx) Optimizes and compiles the expression.
Iter	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.
boolean	shadows(Var v) Checks if the specified is not shadowed by another variable.
java.lang.String	toString()

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

color, removable, remove, returned

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

addText, atomic, checkCtx, checkDbl, checkItr, duplicates, e, ebv, i, indexAccessible, indexEquivalent, sameAs, size, test, uses

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

For

public For(Expr e,
           Var v,
           Var p,
           Var s)

Constructor.

Parameters:

e - variable input

v - variable

p - positional variable

s - score variable

Method Detail

comp

public Expr comp(QueryContext ctx)
          throws QueryException

Description copied from class: Expr

Optimizes and compiles the expression.

Specified by:

comp in class Expr

Parameters:

ctx - query context

Returns:

optimized Expression

Throws:

QueryException - evaluation exception

iter

public Iter iter(QueryContext ctx)

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.

Overrides:

iter in class Expr

Parameters:

ctx - query context

Returns:

resulting item

shadows

public boolean shadows(Var v)

Description copied from class: ForLet

Checks if the specified is not shadowed by another variable.

Overrides:

shadows in class ForLet

Parameters:

v - variable to be checked

Returns:

result of check

toString

public java.lang.String toString()

Specified by:

toString in class ExprInfo

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.

Specified by:

plan in class ExprInfo

Parameters:

ser - serializer

Throws:

java.io.IOException - exception