koala.dynamicjava.interpreter.context
Class VariableContext

java.lang.Object
  |
  +--koala.dynamicjava.interpreter.context.VariableContext

All Implemented Interfaces:

SimpleContext

Direct Known Subclasses:

GlobalContext

public class VariableContext

extends java.lang.Object

implements SimpleContext

This class encapsulates the behaviour of Java scopes.

Inner Class Summary

protected static class	VariableContext.AbstractVariable To store the variables
protected class	VariableContext.Constant To store the constants
protected static class	VariableContext.Link To store one scope
protected static class	VariableContext.LinkFactory To manage the creation of scopes and links
protected static class	VariableContext.Scope A table which maps a string with an object
protected static class	VariableContext.Variable To store the variables

Field Summary

protected VariableContext.Scope	cscope The current scope for variables
protected VariableContext.Scope	scope The current scope
protected VariableContext.Link	scopes The scopes

Constructor Summary

VariableContext()
Creates a new context initialized with an empty initial scope

VariableContext(java.util.Set entries)
Creates a new context initialized with the given entries defined in the initial scope.

Method Summary

void	define(java.lang.String name, java.lang.Object value) Defines a new variable in the current scope
void	defineConstant(java.lang.String name, java.lang.Object value) Defines a new constant variable in the current scope
void	defineVariables(java.util.Set vars) Defines the given variables
void	enterScope() Enters a scope
void	enterScope(java.util.Set entries) Enters a scope and defines the given entries to null.
java.lang.Object	get(java.lang.String name) Returns the value of a variable with the given name
java.util.Map	getConstants() Creates a map that contains the constants in this context
java.util.Set	getCurrentScopeVariableNames() Returns the current scope variables (strings) in a set
java.util.Set	getCurrentScopeVariables() Returns the current scope variables in a set
boolean	isDefinedVariable(java.lang.String name) Tests whether an entry is defined in this context
boolean	isFinal(java.lang.String name) Tests whether a variable is final in this context
java.util.Set	leaveScope() Leaves the current scope
void	set(java.lang.String name, java.lang.Object value) Sets the value of a defined variable
void	setConstant(java.lang.String name, java.lang.Object value) Sets the value of a constant variable in the current scope
void	setVariable(java.lang.String name, java.lang.Object value) Sets the value of a variable in the current scope

Methods inherited from class java.lang.Object

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

Field Detail

scopes

protected VariableContext.Link scopes

The scopes

scope

protected VariableContext.Scope scope

The current scope

cscope

protected VariableContext.Scope cscope

The current scope for variables

Constructor Detail

VariableContext

public VariableContext()

Creates a new context initialized with an empty initial scope

VariableContext

public VariableContext(java.util.Set entries)

Creates a new context initialized with the given entries defined in the initial scope.

Parameters:

entries - a set of string

Method Detail

enterScope

public void enterScope()

Enters a scope

Specified by:

enterScope in interface SimpleContext

enterScope

public void enterScope(java.util.Set entries)

Enters a scope and defines the given entries to null.

Specified by:

enterScope in interface SimpleContext

Parameters:

entries - a set of string

defineVariables

public void defineVariables(java.util.Set vars)

Defines the given variables

Specified by:

defineVariables in interface SimpleContext

leaveScope

public java.util.Set leaveScope()

Leaves the current scope

Specified by:

leaveScope in interface SimpleContext

Returns:

the set of variable defined in this scope

getCurrentScopeVariables

public java.util.Set getCurrentScopeVariables()

Returns the current scope variables in a set

Specified by:

getCurrentScopeVariables in interface SimpleContext

getCurrentScopeVariableNames

public java.util.Set getCurrentScopeVariableNames()

Returns the current scope variables (strings) in a set

Specified by:

getCurrentScopeVariableNames in interface SimpleContext

isDefinedVariable

public boolean isDefinedVariable(java.lang.String name)

Tests whether an entry is defined in this context

Specified by:

isDefinedVariable in interface SimpleContext

Parameters:

name - the name of the entry

isFinal

public boolean isFinal(java.lang.String name)

Tests whether a variable is final in this context

Specified by:

isFinal in interface SimpleContext

Parameters:

name - the name of the entry

Returns:

false if the variable is not final

Throws:

java.lang.IllegalStateException - if the variable is not defined

define

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

Defines a new variable in the current scope

Specified by:

define in interface SimpleContext

Parameters:

name - the name of the new entry

value - the value of the entry

Throws:

java.lang.IllegalStateException - if the variable is already defined

defineConstant

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

Defines a new constant variable in the current scope

Specified by:

defineConstant in interface SimpleContext

Parameters:

name - the name of the new entry

value - the value of the entry

Throws:

java.lang.IllegalStateException - if the variable is already defined

get

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

Returns the value of a variable with the given name

Specified by:

get in interface SimpleContext

Parameters:

name - the name of the value to get

Throws:

java.lang.IllegalStateException - if the variable is not defined

set

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

Sets the value of a defined variable

Specified by:

set in interface SimpleContext

Parameters:

name - the name of the entry

value - the value of the entry

Throws:

java.lang.IllegalStateException - if the variable is not defined or is final

setConstant

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

Sets the value of a constant variable in the current scope

Specified by:

setConstant in interface SimpleContext

Parameters:

name - the name of the entry

value - the value of the entry

setVariable

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

Sets the value of a variable in the current scope

Specified by:

setVariable in interface SimpleContext

Parameters:

name - the name of the entry

value - the value of the entry

getConstants

public java.util.Map getConstants()

Creates a map that contains the constants in this context

Specified by:

getConstants in interface SimpleContext