org.basex.query.xquery.path
Class Path

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

Direct Known Subclasses:

SimpleIterPath

public class Path
extends Arr

Path 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

Expr	root Top expression.

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

expr

Constructor Summary

Path(Expr r, Expr[] p)
Constructor.

Method Summary

Expr	comp(XQContext ctx) Optimizes and compiles the expression.
Path	invertPath(Step curr) Inverts a path.
static Path	invertSIStep(SimpleIterStep sis, Step curr, Expr expr) Inverts a path.
Iter	iter(XQContext ctx) Evaluates the expression and returns an iterator on the resulting items.
java.lang.String	path() Returns a string representation of the path.
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()
boolean	uses(Expr.Using u) Indicates if an expression uses the specified type.

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

Field Detail

root

public Expr root

Top expression.

Constructor Detail

Path

public Path(Expr r,
            Expr[] p)

Constructor.

Parameters:

r - root expression

p - expression list

Method Detail

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

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

invertPath

public Path invertPath(Step curr)

Inverts a path.

Parameters:

curr - current location step

Returns:

inverted path

invertSIStep

public static Path invertSIStep(SimpleIterStep sis,
                                Step curr,
                                Expr expr)

Inverts a path.

Parameters:

sis - SimpleIterStep

curr - current location step

expr - Expression

Returns:

inverted path

uses

public boolean uses(Expr.Using u)

Description copied from class: Expr

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

Overrides:

uses in class Arr

Parameters:

u - using flag

Returns:

result of check

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

path

public java.lang.String path()

Returns a string representation of the path.

Returns:

path as string

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 Arr

Parameters:

ser - serializer

Throws:

java.io.IOException - exception