Ingeniería del So8ware II

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Seminario. Programación Orientada a Aspectos 

Ingeniería del So8ware II 

Pablo Sánchez Barreiro 

D

PTO

. 

DE

 M

ATEMÁTICAS

, E

STADÍSTICA

Y

COMPUTACIÓN 

p.sanchez@unican.es

Este tema se publica bajo Licencia: 

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Table of Contents

1 Introduction: Why we need Aspect-Oriented Programming

2 Aspect-Oriented Programming

3 Current Challenges

4 What AOSD Is Not About

5 AOSD and Related Technologies

6 Conclusions

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Introduction Crosscutting Concerns

Crosscutting Concerns Drawbacks

Happiness

Sadness

Module A Module B Module C Module D Module E

Base Functionality

Fault Tolerance v2.0 Access Control

Encryption

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Case Study: Apache Tomcat

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Motivating example: Access Control

AccessControl class [ ]

+askForCredentials( out username : String, out password : String )

AccessControlView

+getAccess() : Boolean

+getSelectiveAccess( String : String )

AccessControl -name : String -address : String -religion : String -diseases : String [0..*] +getName() : String +getAddress() : String +getReligion() : String +getDiseases() : String [0..*] Student +authenticator «use»

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Motivating example: Access Control

public class Student {

protected String religion;

protected AccessControl authenticator =

new AccessControl();

public String getReligion() {

String result = null;

if (authenticator.getAccess()) { result = this.religion; } // if

return result;

} // getReligion

} // Student

public class Student {

protected String religion;

protected AccessControl authenticator =

new AccessControl();

public String getReligion() {

String result = null;

if (authenticator.getAccess()) { result = this.religion; } // if

return result;

} // getReligion

} // Student

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Motivating example: Access Control

public List<String> getDiseases() { List<String> result = null; if (authenticator.getAccess()) {

result = this.diseases; } // if

return result; } // getDiseases

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Main Shortcoming of Crosscutting Concerns

Happiness

Sadness

Module A Module B Module C Module D Module E Base Functionality

Fault Tolerance v2.0 Access Control

Encryption @#&

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Introduction Conclusions

Conclusions

Scattering

A concern appears spread over several software modules.

Tangling

Several concern appears software modules.

1 Scattering:Decreases encapsulation, (consequently decreases

cohesion),creates redundancies, hinders reutilization of the

crosscutting concern and increase coupling.

2 Tangling:Decreases cohesion, (consequently hampers reutilization),

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Introduction Empirical Evidence

Concern-Oriented Metrics [Sant’Anna et al., 2007]

CDC Concern Diffusion over Classes

CDO Concern Diffusion over Operations

CIC Class-Level Interlacing between Concerns

OOC Operation-Level Overlapping between Concerns

ACC Afferent Coupling between Classes

ECC Efferent Coupling between Classes

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Introduction Empirical Evidence

Concern-Oriented Metrics [Sant’Anna et al., 2007]

AccessControl

class [ ]

+askForCredentials( out username : String, out password : String )

AccessControlView

+getAccess() : Boolean +getSelectiveAccess( String : String )

AccessControl -name : String -address : String -religion : String -diseases : String [0..*] +getName() : String +getAddress() : String +getReligion() : String +getDiseases() : String [0..*] Student +authenticator «use»

CDC CDO CIC OOC

Data Storage (base) 1 4 1 1

AccessControl 3 5 1 1

ACC ECC LCC

Student 0 1 2

AccessControl 1 1 1

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Aspect-Oriented Programming

Aspect-Oriented Programming Principle

Module B Module A Joinpoint Joinpoint Joinpoint Joinpoint

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Access Control Module B Module A Fault Tolerance Encryption Aspect Aspect Aspect

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Access Control Module B Module A Fault Tolerance Encryption Pointcut Pointcut Pointcut

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Aspect-Oriented Programming Aspect-Oriented Weaving

Weaving Process

Base Model

Aspect-Oriented Weaving Process

A sp e ct W e a v e r Pointcut Model Aspect Model

Woven Base Model

C o m m o n C o m p il e r 100101 101100 010101 Compiled Code

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Weaving Process

Concern Identifier Requirements Weaver Concern implementation Aspectual Decomposition Aspectual Recomposition Final System

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Kinds of Aspect-Oriented Weaving

Static Weaving Aspects are woven at compile time [Kiczales et al., 2001].

Load-Time Weaving Aspects are woven at class load-time [Laddad, 2001, Chiba, 2000].

Dynamic Weaving Aspects can be woven and even unwoven at runtime [Pinto et al., 2005, Suv´ee et al., 2003]. It is particulary interesting for context-aware

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Aspect-Oriented Programming Example: Access Control as an Aspect

Access Control With AspectJ

public aspect AccessControlAspect {

pointcut guardedMethods():

call(String Student.getReligion()); String around() : guardedMethods() {

AccessControl guard = new AccessControl(); String returnValue = null;

if (guard.getAccess()) { returnValue = proceed(); } // if

return returnValue; } // around guardedMethods

} // AccessControlAspect

public aspect AccessControlAspect { pointcut guardedMethods():

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Aspect-Oriented Programming Example: Access Control as an Aspect

A Clean Student Class

public class Student {

protected String religion; public String getReligion() {

return this.religion; } // getReligion

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Aspect-Oriented Programming Quantification

Wildcard-based Quantified Pointcuts

public aspect QuantifiedAccessControlAspect {

pointcut guardedMethods(): call(* Student.get*(..)); Object around() : guardedMethods() {

AccessControl guard = new AccessControl(); Object returnValue = null;

if (guard.getAccess()) { returnValue = proceed(); } // if return returnValue; } // around guardedMethods } // QuantifiedAccessControlAspect

public aspect QuantifiedAccessControlAspect {

pointcut guardedMethods(): call(* Student.get*(..)); Object around() : guardedMethods() {

if (guard.getAccess()) { returnValue = proceed(); } // if return returnValue; } // around guardedMethods } // QuantifiedAccessControlAspect

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Aspect-Oriented Programming Annotation-based Quantification

Annotation-based Quantified Pointcuts

public class Student {

protected String religion;

@AccessControlRequired

public String getReligion() { return this.religion; } // getReligion

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Aspect-Oriented Programming Annotation-based Quantification

Annotation-based Quantified Pointcuts

public aspect AnnotationBasedAspect {

call(@AccessControlRequired * *.*(..));

Object around() : guardedMethods() {

if (guard.getAccess()) { returnValue = proceed(); } // if return returnValue; } // around guardedMethods } // AnnotationBasedAspect

public aspect AnnotationBasedAspect { pointcut guardedMethods():

call(@AccessControlRequired * *.*(..));

Object around() : guardedMethods() {

if (guard.getAccess()) { returnValue = proceed(); } // if return returnValue; } // around guardedMethods } // AnnotationBasedAspect

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Aspect-Oriented Programming Reflection

Some Basic & Free Reflection

A c c e s s C o n t r o l c l a s s [ ] + a s k F o r C r e d e n t i a l s ( o u t u s e r n a m e : S t r i n g , o u t p a s s w o r d : S t r i n g ) A c c e s s C o n t r o l V i e w + g e t A c c e s s ( ) : B o o l e a n + g e t S e l e c t i v e A c c e s s ( S t r i n g : S t r i n g ) A c c e s s C o n t r o l - n a m e : S t r i n g - a d d r e s s : S t r i n g - r e l i g i o n : S t r i n g - d i s e a s e s : S t r i n g [ 0 . . * ] + g e t N a m e ( ) : S t r i n g + g e t A d d r e s s ( ) : S t r i n g + g e t R e l i g i o n ( ) : S t r i n g + g e t D i s e a s e s ( ) : S t r i n g [ 0 . . * ] S t u d e n t + a u t h e n t i c a t o r « u s e »

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Some Basic & Free Reflection

public aspect ReflectionAccessControlAspect {

AccessControl guard =new AccessControl(); String returnValue = null;

if (guard.getSelectiveAccess( thisJoinPoint.getSignature(). getName())) { returnValue = proceed(); } // if returnreturnValue; } // around guardedMethods } // ReflectionAccessControlAspect

public aspect ReflectionAccessControlAspect { pointcutguardedMethods():

call(String Student.getReligion()); Stringaround() : guardedMethods() {

if(guard.getSelectiveAccess( thisJoinPoint.getSignature(). getName())) { returnValue = proceed(); } // if return returnValue; } // around guardedMethods } // ReflectionAccessControlAspect

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Concern-Oriented Metrics Revisited

AccessControlAspect

class [ ]

+askForCredentials( out username : String, out password : String ) AccessControlView -name : String -address : String -religion : String -diseases : String [0..*] +getReligion() : String +getName() : String +getAddress() : String

+getDiseases( diseases : String [0..*] ) Student

+getAccess() : Boolean +getSelectiveAccess( String : String )

AccessControl

«crosscut»

CDC CDO CIC OOC

Data Storage (base) 1 (1) 4 (4) 0 (1) 0 (1)

AccessControl 2 (2) 3 (5) 0 (1) 0 (1)

ACC ECC LCC

Student 1 (0) 0 (1) 1 (2)

AccessControl 0 (1) 2 (1) 1 (1)

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Current Challenges

Current Hot Research Topics on AOSD

<<CallBehavior>> calculateDiscount <<CallBehavior>> minus first proceed <<proceed>> price price : Real checkOut(..) (.*):(.*) <?cart>(.*) : ShoppingCart (.*):(.*) newCreditCard(..) <?ws>(.*): WebServiceBank termsAndConditionsOfSeasonalRebate [*] <?jp>: approveCredit(<?cc>(.*):PaymentMethod, <?price>(.*):Real)) <?cc>(.*):CreditCard ?jp ?price

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What AOSD is not about

Table of Contents

4 What AOSD Is Not about

6 Conclusions

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What AOSD is not about AOSD is not View-Based Software Development

AOSD is not View-Based Software Development

class addItem

UserGUI IShop ShoppingCart

+ books 0 ..*

+ addItem (book :Book , amount :int ) << theme >>

AddItem

<< theme >>

CheckOut

class checkOut

UserGUI IShop ShoppingCart

Delivery + checkOut () IDelivery Bank IBank sdcheckOut

UserGUI ShoppingCart Delivery Bank checkDelivery (address = -,weight = -,size = -)

approveCredit (ccNumber = -,amount = -)

merge Books

sdaddItem

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What AOSD is not about AOSD is not Feature-Oriented Software Development

AOSD is not Feature-Oriented Software Development

Architecture

class [ ]

SmartEnergyMng

+openWindow( id : Integer ) +closeWindow( id : Integer ) +adjustTemperature( id : Integer, temp : float )

Gateway

+operationMode : TempUnits

ThermometerCtrl Sensor InitialModel

+changeValue( id : Integer, value : float ) +emergence( a : Sensor, value : float )

Gateway

+id : Integer

+setValue( value : float )

Actuator

+id : Integer

+getValue() : float

Sensor

HeaterMng

+adjustTemperature( id : Integer, temp : float )

Gateway +units : TempUnits +set( t : float ) HeaterCtrl FAHRENHEIT CELSIUS «enumeration» TempUnits Actuator WindowMng +openWindow( id : Integer ) +closeWindow( id : Integer ) Gateway +open() +close() WindowCtrl Actuator LightMng +switchLight( id : Integer ) Gateway +switch() LightCtrl Actuator +indoorTherm 1 +outdoorTherm 1 +sensors 0..* +actuators 0..* +gtw 0..1 +heaters 1..* +windows 1..* +lights 1..* «merge» «merge» «merge» «merge» «merge»

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AOSD and Related Technology

AOSD in Industry

1 Spring framework for Enterprise Java.

2 SpringSource dm Server, SpringSource tc Server, Spring Roo y

Magma.

3 GlassBox, Perf4J, Contract4J, JXInsight, MaintainJ.

4 Websphere, MySQL, JBoss, Oracle Toplink,

J2ME [Rashid et al., 2010].

5 Siemens Healthcare [Rashid et al., 2010].

6 Motorola Weavr [Cottenier et al., 2007].

7 Oficina Virtual Fundaci´on Retevisi´on [Pinto et al., 2005]

8 Digital Publishing [de Beeck et al., 2009].

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Conclusions

Referencias II

Brichau, J. and D‘Hondt, T. (2005).

Introduction to Aspect-Oriented Software Development.

Deliverable D17 AOSD-Europe-VUB-02, AOSD-Europe Network of Excellence, Brussels.

Chiba, S. (2000).

Load-Time Structural Reflection in Java.

In Bertino, E., editor,Proc. of the 14th European Conference on Object-Oriented Programming (ECOOP), pages 313–336, Sophia Antipolis and Cannes (France).

Colyer, A., Clement, A., Harley, G., and Webster, M. (2004).

Eclipse AspectJ: Aspect-Oriented Programming with AspectJ and the Eclipse AspectJ Development Tools.

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References

Referencias III

Cottenier, T., van den Berg, A., and Elrad, T. (2007).

Motorola WEAVR: Aspect and model-Driven Engineering.

Journal of Object Technology (JOT), 6(7):51–88.

de Beeck, S. O., Landuyt, D. V., Truyen, E., and Joosen, W. (2009).

Building a Next-Generation Digital News Publishing Platform with AOSD.

InProc. of the 8th Int. Conference on Aspect-Oriented Software Development (AOSD), Charlottesvile (Virginia, USA).

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References

Referencias IV

Douence, R., Fradet, P., and S¨udholt, M. (2002).

A Framework for the Detection and Resolution of Aspect Interactions. In Batory, D. S., Consel, C., and Taha, W., editors,Proc. of the Int. Conference on Generative Programming and Component Engineering (GPCE), volume 2487 ofLNCS, pages 173–188, Pittsburgh,

(Pennsylvania, USA).

Douence, R., Fradet, P., and S¨udholt, M. (2004).

Composition, Reuse and Interaction Analysis of Stateful Aspects. InProc. of the 3rd Int. Conference on Aspect-Oriented Software Development (AOSD), pages 141–150, Lancaster (UK).

Elrad, T., Ak¸sit, M., Kiczales, G., Lieberherr, K., and Ossher, H. (2001).

Discussing Aspects of AOP.

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References

Referencias V

Filman, R. E., Elrad, T., Clarke, S., and Ak¸sit, M., editors (2004).

Aspect-Oriented Software Development. Addison-Wesley, Boston.

Fuentes, L., G´amez, N., and S´anchez, P. (2009).

Aspect-Oriented Design and Implementation of Context-Aware Pervasive Applications.

Innovations in Systems and Software Engineering, 5(1):79–93.

Hannemann, J. and Kiczales, G. (2002).

Design Pattern Implementation in Java and AspectJ. InProc. of the 17th Int. Conference on Object-Oriented

Programming, Systems, Languages, and Applications (OOPSLA), pages 161–173, Seattle (Washington, USA).

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References

Referencias VI

Kiczales, G., Hilsdale, E., Hugunin, J., Kersten, M., Palm, J., and Griswold, W. G. (2001).

An Overview of AspectJ.

In Knudsen, J. L., editor, Proc. of the 15th European Conference on Object-Oriented Programming (ECOOP), volume 2072 of Lecture Notes in Computer Science, pages 327–353, Budapest (Hungary).

Kiczales, G., Lamping, J., Mendhekar, A., Maeda, C., Lopes, C. V., Loingtier, J.-M., and Irwin, J. (1997).

Aspect-Oriented Programming.

In Ak¸sit, M. and Matsuoka, S., editors,Proc. of the 11th European Conference on Object-Oriented Programming (ECOOP), volume 1241 ofLecture Notes in Computer Science, pages 220–242,

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References

Referencias VII

Kienzle, J. and G´elineau, S. (2006).

AO challenge - Implementing the ACID properties for Transactional Objects.

In Filman, R. E., editor,Proc. of the 5th Int. Conference on Aspect-Oriented Software Development (AOSD), pages 202–213.

Laddad, R. (2001).

I want my AOP! Java World,

http://www.javaworld.com/javaworld/jw-01-2002/jw-0118-aspe

Ostermann, K. (2008).

Reasoning about Aspects with Common Sense.

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References

Referencias VIII

Ostermann, K., Mezini, M., and Bockisch, C. (2005).

Expressive Pointcuts for Increased Modularity.

In Black, A. P., editor,Proc. of the 19th European Conference on Object-Oriented Programming (ECOOP), volume 3586 of LNCS, pages 214–240, Glasgow (UK).

Pinto, M., Fuentes, L., and Troya, J. M. (2005).

A Dynamic Component and Aspect-Oriented Platform.

Computer Journal, 48(4):401–420.

Rashid, A., Cottenier, T., Greenwood, P., Chitchyan, R., Meunier, R., Coelho, R., S¨udholt, M., and Joosen, W. (2010).

Aspect-Oriented Software Development in Practice: Tales from AOSD-Europe.

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References

Referencias IX

Sant’Anna, C., Figueiredo, E., Garcia, A. F., and de Lucena, C. J. P. (2007).

On the Modularity of Software Architectures: A Concern-Driven Measurement Framework.

In Oquendo, F., editor,Proc. of the 1st European Conference on Software Architecture (ECSA), pages 207–224, Aranjuez (Spain).

Suv´ee, D., Vanderperren, W., and Jonckers, V. (2003).

JAsCo: an Aspect-Oriented Approach Tailored for Component-Based Software Development.

InProc. of the 2nd Int. Conference on Aspect-Oriented Software Development (AOSD), pages 21–29, Boston (Massachusetts, USA).

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Questions

http://personales.unican.es/sanchezbp/teaching/ao/accesscontrol.zip

http://www.aosd-europe.net

http://www.javaworld.com/javaworld/jw-01-2002/jw-0118-aspe

Ingeniería del So8ware II

Seminario. Programación Orientada a Aspectos

Crosscutting Concerns Drawbacks

Motivating example: Access Control

AccessControlView

Motivating example: Access Control

Motivating example: Access Control

Conclusions

Concern-Oriented Metrics [Sant’Anna et al., 2007]

Concern-Oriented Metrics [Sant’Anna et al., 2007]

AccessControlView

Table of Contents

Aspect-Oriented Programming Principle

Weaving Process

Access Control With AspectJ

A Clean Student Class

Annotation-based Quantified Pointcuts

Some Basic & Free Reflection

Concern-Oriented Metrics Revisited

AccessControl

Table of Contents

Current Hot Research Topics on AOSD

AOSD is not View-Based Software Development

UserGUI IShop ShoppingCart

AOSD is not Feature-Oriented Software Development

Gateway

Table of Contents

AOSD in Industry

Table of Contents

Table of Contents

Referencias II

Referencias III

Referencias IV

Referencias V

Referencias VI

Referencias VII

Referencias VIII

Referencias IX

Seminario. Programación Orientada a Aspectos 