org.basex.query.xquery.expr
Class Unary

java.lang.Object
  org.basex.query.ExprInfo
      org.basex.query.xquery.expr.Expr
          org.basex.query.xquery.expr.Single
              org.basex.query.xquery.expr.Unary

public final class Unary
extends Single

Unary Expression.

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.Single

expr

Constructor Summary

Unary(Expr e, boolean min)
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.
void	plan(Serializer ser) Recursively sends the abstract syntax of this expression to the specified serializer.
Type	returned() Indicates if an expression returns the specified type.
java.lang.String	toString()

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

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

Unary

public Unary(Expr e,
             boolean min)

Constructor.

Parameters:

e - expression

min - minus flag

Method Detail

comp

public Expr comp(XQContext ctx)
          throws XQException

Description copied from class: Expr

Optimizes and compiles the expression.

Overrides:

comp in class Single

Parameters:

ctx - query context

Returns:

optimized Expression

Throws:

XQException - evaluation exception

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

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 Single

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.

Overrides:

plan in class Single

Parameters:

ser - serializer

Throws:

java.io.IOException - exception