org.basex.query.xquery.expr
Class If

java.lang.Object
  org.basex.query.ExprInfo
      org.basex.query.xquery.expr.Expr
          org.basex.query.xquery.expr.Arr
              org.basex.query.xquery.expr.If

public final class If
extends Arr

FLWOR Clause.

Author:

Workgroup DBIS, University of Konstanz 2005-08, ISC License, Christian Gruen

Nested Class Summary

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

Expr.Return, Expr.Using

Field Summary

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

expr

Constructor Summary

If(Expr e, Expr t, Expr s)
Constructor.

Method Summary

Expr	comp(XQContext ctx) Optimizes and compiles the expression.
Iter	iter(XQContext ctx) Evaluates the expression and returns an iterator on the resulting items.
Type	returned() Indicates if an expression returns the specified type.
java.lang.String	toString()

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

plan, uses

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

e, i

Methods inherited from class org.basex.query.ExprInfo

color, info, name

Methods inherited from class java.lang.Object

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

Constructor Detail

If

public If(Expr e,
          Expr t,
          Expr s)

Constructor.

Parameters:

e - expression

t - then clause

s - else clause

Method Detail

iter

public Iter iter(XQContext ctx)
          throws XQException

Description copied from class: Expr

Evaluates the expression and returns an iterator on the resulting items.

Specified by:

iter in class Expr

Parameters:

ctx - query context

Returns:

resulting item

Throws:

XQException - evaluation exception

comp

public Expr comp(XQContext ctx)
          throws XQException

Description copied from class: Expr

Optimizes and compiles the expression.

Overrides:

comp in class Arr

Parameters:

ctx - query context

Returns:

optimized Expression

Throws:

XQException - evaluation exception

returned

public Type returned()

Description copied from class: Expr

Indicates if an expression returns the specified type. Called by the compiler to check if expressions can be reformulated. null is returned by default.

Overrides:

returned in class Arr

Returns:

result of check

toString

public java.lang.String toString()

Specified by:

toString in class ExprInfo