org.basex.query.util

Class VarContext

java.lang.Object

org.basex.data.ExprInfo

org.basex.query.util.VarContext

public final class VarContext
extends ExprInfo

This class references all in-scope variables.

Author:

BaseX Team 2005-12, BSD License, Christian Gruen

Constructor Summary

Constructors

Constructor and Description
VarContext()

Method Summary

Methods

Modifier and Type	Method and Description
void	add(Var v) Adds a local variable.
VarStack	cache(int c) Creates a new variable stack and returns the old one.
void	checkUp() Checks if none of the global variables contains an updating expression.
Var	get(QNm var) Returns a variable with the specified name.
Var	get(Var name) Returns a variable instance with the same id.
VarStack	globals() Returns the global variables.
VarStack	locals() Returns the local variables.
void	plan(Serializer ser) Serializes the expression tree.
void	reset(VarStack l) Resets the local variables to the specified instance.
int	size() Returns the current number of local variables.
void	size(int s) Sets the number of local variables to the specified value.
java.lang.String	toString()
void	updateGlobal(Var v) Adds or replaces a global variable.

Methods inherited from class org.basex.data.ExprInfo

description, info

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

VarContext

public VarContext()

Method Detail

globals

public VarStack globals()

Returns the global variables.

Returns:

global variables

locals

public VarStack locals()

Returns the local variables.

Returns:

local variables

cache

public VarStack cache(int c)

Creates a new variable stack and returns the old one.

Parameters:

c - stack capacity

Returns:

local variables

reset

public void reset(VarStack l)

Resets the local variables to the specified instance.

Parameters:

l - local variables

updateGlobal

public void updateGlobal(Var v)

Adds or replaces a global variable.

Parameters:

v - variable to be added

add

public void add(Var v)

Adds a local variable.

Parameters:

v - variable

get

public Var get(QNm var)

Returns a variable with the specified name.

Parameters:

var - variable

Returns:

variable

get

public Var get(Var name)

Returns a variable instance with the same id.

Parameters:

name - variable name

Returns:

variable

checkUp

public void checkUp()
             throws QueryException

Checks if none of the global variables contains an updating expression. Called by the QueryParser.

Throws:

QueryException - query exception

plan

public void plan(Serializer ser)
          throws java.io.IOException

Description copied from class: ExprInfo

Serializes the expression tree.

Specified by:

plan in class ExprInfo

Parameters:

ser - serializer

Throws:

java.io.IOException - I/O exception

size

public int size()

Returns the current number of local variables.

Returns:

number of variables

size

public void size(int s)

Sets the number of local variables to the specified value.

Parameters:

s - number of variables to be set

toString

public java.lang.String toString()

Specified by:

toString in class ExprInfo