org.onemind.commons.java.datastructure
Class NametableStack

java.lang.Object
  org.onemind.commons.java.datastructure.NametableStack

public class NametableStack
extends java.lang.Object

A nametable stack contains key-value mapping that has a scope. A new scope can be opened for putting new mappings and all the mappings added in this scope can be wiped out easily with a closeScope command. In effect this is like a stack of Maps, hence the name NametableStack. NOTE: the implementation use a map and list to achieve the behaviour.

Version:

$Id: NametableStack.java,v 1.7 2005/06/22 22:57:37 thlee Exp $ $Name: $

Author:

TiongHiang Lee (thlee@onemindsoft.org)

Nested Class Summary

private static class

NametableStack.LocalNametable The local nametable defines a scope where local variables mask out the global variables, but the global variable can still be accessed.

Field Summary

private java.util.ArrayList	_list the list of maps *
private static java.util.logging.Logger	_logger the logger *
private Nametable	_nametable the map *

Constructor Summary

NametableStack()

NametableStack(java.util.Map m)

Method Summary

java.lang.Object	access(java.lang.String name) Resolve the value associated with key name
java.util.Map	asMap() Return map representation of the nametable stack
java.lang.Object	assign(java.lang.String name, java.lang.Object value) Assign name/value pair
void	closeLocalScope(int i)
void	closeScope(int l) Close a scope
boolean	containsName(java.lang.String name) Whether the map contains key name
void	declare(java.lang.String name, java.lang.Object value) Declare name value pair
int	newLocalScope()
int	newScope() Open a new scope for mappings.
java.lang.String	toString()

Methods inherited from class java.lang.Object

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

Field Detail

_logger

private static final java.util.logging.Logger _logger

the logger *

_nametable

private Nametable _nametable

the map *

_list

private java.util.ArrayList _list

the list of maps *

Constructor Detail

NametableStack

public NametableStack()

NametableStack

public NametableStack(java.util.Map m)

Parameters:

m - the initial mapping

Method Detail

newScope

public int newScope()

Open a new scope for mappings. Return an integer that represents a scope id

Returns:

the new scope

newLocalScope

public int newLocalScope()

closeLocalScope

public void closeLocalScope(int i)

closeScope

public void closeScope(int l)

Close a scope

Parameters:

l - the scope id

declare

public void declare(java.lang.String name,
                    java.lang.Object value)

Declare name value pair

Parameters:

name -

value -

assign

public java.lang.Object assign(java.lang.String name,
                               java.lang.Object value)

Assign name/value pair

Parameters:

name -

value -

Returns:

access

public java.lang.Object access(java.lang.String name)

Resolve the value associated with key name

Parameters:

name - the key

Returns:

the value associated with key

containsName

public boolean containsName(java.lang.String name)

Whether the map contains key name

Parameters:

name - the key

Returns:

true if map contains key name

asMap

public java.util.Map asMap()

Return map representation of the nametable stack

Returns:

the map

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object