tom.library.sl
Class AbstractStrategy

java.lang.Object
  tom.library.sl.AbstractStrategy

All Implemented Interfaces:

Strategy, Visitable

Direct Known Subclasses:

AbstractStrategyBasic, AbstractStrategyCombinator

public abstract class AbstractStrategy
extends Object
implements Strategy

Partial implementation of the strategy interface that implements most of the visit methods. This class is extended by the two abstract classes AbstractStrategyBasic and AbstractStrategyCombinator that can be used to implement respectively new basic transformations (like a rewrite rule system) and new strategy combinators (like the All strategy).

It is not advised to implement directly this abstract class.

Field Summary

protected Environment

environment Environment of the strategy application

Constructor Summary

AbstractStrategy()

Method Summary

Object	getAncestor() Get the current ancestor
Environment	getEnvironment() Get a reference to the current environment.
Position	getPosition() Get the current position
Object	getRoot() Get the current root.
Object	getSubject() Get the current subject
void	init(Introspector introspector) Initialize the Strategy
static void	init(Strategy s, Environment env) Initialize the Strategy by providing the environment and the strategy
void	setEnvironment(Environment env) Set up a new environment.
void	setRoot(Object any) Set up the current root.
void	setSubject(Object any) Set up the current subject
<T extends Visitable> T	visit(Environment envt) Executes the strategy in the given environment (on its current subject).
Object	visit(Environment envt, Introspector i) Executes the strategy in the given environment (on its current subject).
<T extends Visitable> T	visit(T any) Visits the subject any by providing the environment
<T> T	visit(T any, Introspector i) Visits the subject any by providing the introspector
<T extends Visitable> T	visitLight(T any) Visits the subject any in a light way (without environment)

Methods inherited from class java.lang.Object

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

Methods inherited from interface tom.library.sl.Strategy

visit, visitLight

Methods inherited from interface tom.library.sl.Visitable

getChildAt, getChildCount, getChildren, setChildAt, setChildren

Field Detail

environment

protected Environment environment

Environment of the strategy application

Constructor Detail

AbstractStrategy

public AbstractStrategy()

Method Detail

visit

public <T extends Visitable> T visit(Environment envt)
                          throws VisitFailure

Executes the strategy in the given environment (on its current subject). This method can only be used inside user strategies to execute another strategy but with the current environment of the user strategy.

Specified by:

visit in interface Strategy

Parameters:

envt - the environment where execute the strategy.

Throws:

VisitFailure - if visit fails

visit

public <T extends Visitable> T visit(T any)
                          throws VisitFailure

Visits the subject any by providing the environment

Specified by:

visit in interface Strategy

Parameters:

any - the subject to visit.

Throws:

VisitFailure - if visit fails

visit

public Object visit(Environment envt,
                    Introspector i)
             throws VisitFailure

Executes the strategy in the given environment (on its current subject). This method can only be used inside user strategies to execute another strategy but with the current environment of the user strategy.

Specified by:

visit in interface Strategy

Parameters:

envt - the environment where execute the strategy.

i - the introspector

Throws:

VisitFailure - if visit fails

visitLight

public <T extends Visitable> T visitLight(T any)
                               throws VisitFailure

Visits the subject any in a light way (without environment)

Specified by:

visitLight in interface Strategy

Parameters:

any - the subject to visit

Throws:

VisitFailure - if visitLight fails

visit

public <T> T visit(T any,
                   Introspector i)
        throws VisitFailure

Visits the subject any by providing the introspector

Specified by:

visit in interface Strategy

Parameters:

any - the subject to visit.

i - the introspector

Throws:

VisitFailure - if visit fails

getEnvironment

public Environment getEnvironment()

Get a reference to the current environment.

Specified by:

getEnvironment in interface Strategy

Returns:

the current environment

Throws:

RuntimeException - if the environment is not initialized

setEnvironment

public void setEnvironment(Environment env)

Set up a new environment.

Specified by:

setEnvironment in interface Strategy

Parameters:

env - the environment to set up.

getRoot

public Object getRoot()

Get the current root.

Returns:

the current root

setRoot

public void setRoot(Object any)

Set up the current root.

Parameters:

any - the current root

getSubject

public Object getSubject()

Get the current subject

Returns:

the current subject

setSubject

public void setSubject(Object any)

Set up the current subject

Parameters:

any - the subject to set up

getPosition

public Position getPosition()

Get the current position

Returns:

the current application position

getAncestor

public Object getAncestor()

Get the current ancestor

Returns:

the current ancestor

init

public void init(Introspector introspector)

Initialize the Strategy

init

public static void init(Strategy s,
                        Environment env)

Initialize the Strategy by providing the environment and the strategy

Parameters:

s - the strategy

env - the environment