Problems we can Solve with Power-Generics Tut24 power... · Title: Microsoft PowerPoint - ICSE09 Tut24 power-generics StanJ 3April09 Author: dcssj Created Date: 4/8/2009 3:38:02 PM

1

1

Stan JarzabekNational University of Singapore

Simple yet Effective Reuse beyond Components

Problems we can Solve withProblems we can Solve withPowerPower--GenericsGenerics

31st International Conference on Software Engineering

Tutorial 24

2ICSE’09 Tutorial 24 Copyright (C) 2009 Stan Jarzabek

TemplatesTemplatesA template represents a group of similar classes in generic, adaptable form:

With power-generics, we want to do the same for:– Any family of similar software products– Any group of similar program structures

Files, directories, components, patterns of components, etc.

Stack <T>Queue<T>Set<T>Sort <T>Search<T>

IntStack

template

instantiation

ShortStack

IntQueue

ShortStack

2


What is What is powerpower--genericsgenerics??Role Playing Games (RPG) on mobile phones

The four RPGs are similar

RPGs running on many mobile phones are also similar

Jump FeedingDigGem

Hunt

Let’s have a generic RPG!


What is a What is a generic RPGgeneric RPG??A generic RPG is a parameterized RPG that can be adapted to DigGem, Haunt, …Key: observe repetitions across RPGs– similarities and differences

variant features

generic RPG

game

derivation

parameters

DigGemDigGem

HuntHunt

JumpJump

FeedingFeeding

3


What is What is powerpower--genericsgenerics??For any group of similar program structureswe want a generic, adaptable form– similar files, directories, …, software products

CreateStaffUser Interface

CreateStaffBusiness Logic

Staff Table Project Table

CreateProjectBusiness Logic

CreateProjectUser Interface

Task Table

CreateTaskBusiness Logic

CreateTaskUser Interface

Create[E].UI

Create[E].BL

Create[E].DB


Questions:Questions:1. How are power-generics useful? In what situations

we can benefit from them?– RAD? Maintenance? Reuse?

2. How to achieve power-generics?3. How do they compare to classical software reuse

– Architecture-centric, component based

4. How to make power-generics a practical software development/maintenance method?

5. Any evidences?

4


Reuse beyond componentsReuse beyond componentsAre you using or considered any of these techniques:

Classes and components.NET, JEEModel-driven approachDesign patternsPreprocessing, macrosConfiguration files, parameter tablesAnt, make, other build toolsXVCL – helps to achieve similar goals– XML-based Variant Configuration Language– parameterized, adaptable components


Is XVCL relevant to you?Is XVCL relevant to you?Do you develop multiple software product variants for:– different customers– market segments– platforms

Does this involve much repetitive work?Do you maintain all these product variants?Does this involve much repetitive work?

If some answers are ‘yes’ – you already are in reuse business, software Product Lines (SPL)

5


WhatWhat’’s our challenge in s our challenge in

software development?software development?


What do these structures have in common?What do these structures have in common?

They are large and complex structuresThey were built without modern technologies!But it took huge effort and cost to build them– 27 years to build each pyramid– thousands people died building them

12th century

2000 BC

10th - 15th century887 moailarge stone statues20th century

6


IsnIsn’’t software situation similar?t software situation similar?We can develop large and complex software:– IBM OS (1960’s)– military software is huge, complex, must be reliable– WINDOWS (close to 100 million LOC) – most businesses today depend on complex software systems

Important questions:How can we develop software at lower cost, with higher success rate? – Do we have right tools for that?

How can we tackle even more complex systems?Ultra-Large-Scale Systems: systems of systems (billions LOC)


Software engineering challengesSoftware engineering challengesdespite new technologies and many successes:

Software projects are often unpredictable– many projects run out of schedule and budget, 25% of large projects are

never completed

Maintenance cost up to 80% of computing cost– change is hard, evolution is hard

Reuse has not become a standard practice

Outsourcing: a leading software development technique – US$ 100 billion in 2005, growing trend

7


Questions:Questions:1. How are power-generics useful? In what

situations we can benefit from them?– RAD? Maintenance? Reuse?

2. How to achieve power-generics?3. How do they compare to classical software reuse

– Architecture-centric, component based

4. How to make power-generics a practical software development/maintenance method?

5. Any evidences?


ExamplesExamples

8


RoleRole--Playing Games (RPG)Playing Games (RPG)

The four RPGs are similarRPGs running on many mobile phones are also similar

A software Product Line (SPL)

Jump FeedingDigGem

Hunt

Let’s reuse!


Market forces: good reasons to reuseMarket forces: good reasons to reuseSimilar RPGs must run on many types of mobile devices and must perform well

Many brands and models of mobile devices– differ in platforms, communication protocols, display

units, memory size, etc.

– 640 x 200 color screen vs. 100 x 80 mono display

– 80M memory vs. less than 100kb memory

– J2ME MIDP2.0 vs. MIDP1.0

Development cost, time-to-market are important

9


Explosion of RPG product variantsExplosion of RPG product variants

A nightmare and opportunity for mobile software vendors:

How are RPGs similar? common featuresHow are RPGs different? variant features

Climb FeedingDigGem Hunt

Nokia E65 Nokia E70 Nokia E90 W890i W910i Motorola ….

RPGs

mobile phones


Conventional techniquesConventional techniques

Climb FeedingDigGem Hunt

Nokia E65 Nokia E70 Nokia E90 W890i W910i Motorola ….

RPGs

mobile phones

reuse with game engines

reuse with power-generics

portability with power-generics

portability with platform mechanisms

Game engines and platform mechanisms

manualworkmanual

work

10


Project Collaboration Project Collaboration EnvirEnvir (PCE)(PCE)

PCE stores staff, project data, facilitates project progress monitoring, communication in the team, etc.

e.g., Module Staff: allows the user to create, edit, and update data about staff members, assign staff members to projects, etc.


PCE product variantsPCE product variants

PCEMyTeam

PCESmall-1

PCESmall-2

PCESmall-3

PCEBig-1

PCEBig-2

PCEBig-3

PCEBig-2-Dept1

PCEBig-2-Dept2

PCEBig-2-Dept3

PCEAgile

PCEWaterfall

PCEAgile-Small

PCEAgile-Big

reuse

11


Comments on product evolutionComments on product evolutioneach PCE product variant implements:– common features shared by all PCEs– features shared with some of the PCEs– some unique new features

implementation of the same feature across various PCEs may vary

we would like to reuse as much as possible

How do we manage product evolution?How do we manage product evolution?


Conventional reuseConventional reuse

12


An RPG Product Line: RPGAn RPG Product Line: RPG--PLPL

Understand what’s similar and what’s different among RPGs

Design a reusable Product Line Architecture – PLA

Develop (derive) new RPGs from the RPG-PLA (reuse)

Maintain existing RPGs via RPG-PLA

HuntDigGem JumpDigGem

Jump

FeedingFeeding


Two dimensions of variability– Game functionality variants– Mobile phone platform variants

Variability in Variability in RPGsRPGs

13


PLA design and product derivationPLA design and product derivation

Domain experts

PLA

product developmentProduct development team

Feedback

userrequirements

DigGem

for Nokia

domain engineering

domainknowledge existing systems in a

domain

PLA design and evolution


Reuse: RPGReuse: RPG--PLAPLAHow are RPGs similar and different? – business-oriented analysis variability in a domain– observe repetitions across similar RPGs

Design generic PLA that can be reused across games after suitable adaptations

variant features

DigGemDigGem

HuntHunt

JumpJump

FeedingFeeding

RPG-PLA

game

derivation

reusable componentsreusable components

14


What are our strategies for What are our strategies for

managing product variants?managing product variants?


Strategies for evolution and reuseStrategies for evolution and reusestrategy 1: brut-force evolution

– ignore similarities among PCEs and develop and maintain each PCE as a separate product

strategy 2: ad hoc reuse by copy/modify– store PCE component versions in CVS or SVN– copy and modify files and directories to reuse already

implemented features– implement new features needed in new product variant

what problems?

15


Problems of ad hoc reuseProblems of ad hoc reuse

many PCE products need be maintained

many component versions in CVS

– which components implement which features?

– which component versions will fit new PCE?

manual, error-prone and expensive reuse:

– component selection, adaptation, integration, testing


Strategy 3: allStrategy 3: all--inin--one productone productimplement all PCEs in a single, parameterized product

by setting parameters we obtain required PCE

PCEPCE--11

PCEPCE--22

PCEPCE--33

PCEPCE--44

16


Techniques for allTechniques for all--inin--one strategyone strategy

conditional compilation

commenting out feature code

configuration parameter files/tables

build tools such as Ant, make …

design patterns

Model-Based Development

….


ExamplesExamplesfor( int i=0; i < yearTemp.size(); i++ ) { . . .#If ( FeatureConfiguration.DelegationLock&& FeatureConfiguration.OperationLock )// Code when both features are selected#else if ( FeatureConfiguration.DelegationLock )// Code when delegationLock is selected#else if ( FeatureConfiguration.OperationLock )// Code when operationLock is selected}. . .

/* code for PCEAgile ….. */

/* code for PCEBig ….. */

17


Techniques: AntTechniques: Ant<project name="webfee" basedir="." default="main">. . .<target name="copy‐src" depends="create‐folders">. . .<!‐‐ Copy java classes of Feature DownloadPaymentDetail ‐‐><copy todir="${src.dir}"><fileset dir="${core‐src.dir}/${DownloadPaymentDetail}" /></copy>. . .</target><target name="copy‐webpage" depends="create‐folders">. . .<!‐‐ Copy webpages of Feature DownloadPaymentDetail ‐‐>

<copy todir="${web‐root.dir}"><fileset dir="${core‐webpage.dir}/${DownloadPaymentDetail}" /></copy>. . .</target>. . .<project>


Problems of strategy 3Problems of strategy 3Many inter-related parametersOne feature implemented in many placesDifficult to understand code instrumented with many parametersTime-consuming, error-prone customizationsDifficult to maintain, enhanceAs the number of product variants grows,

problems accumulate

18


1 function editable_form($form, $id=0, $relModID=null, $Container=null, $ContainerID=null)

2 { global $module_name, $attributes; If($form==”Edit”){ $msg=” Please modify the $module_name data”; $title="Edit $module_name"; $nextAction=”saveChanges”; } elseif ($form==”createInsideContainer”){ $msg=” Please enter the $module_name data”; $title="New Composed $module_name "; $nextAction=”saveInstanceInsideContainer”; } elseif ($form=="copy"){ $msg="Please enter the ".$module_name." data"; $title="Copy ".$module_name; $nextAction="saveCopy"; }else{ $msg=” Please enter the $module_name data”; $title="New $module_name "; $nextAction=”saveInstance”; }

3 If($form==”Edit”){ //check user has rights to edit instance… } elseif ($form==”createInsideContainer”){ //check user has rights to edit container… }elseif($form=="copy"){ //retrieve data to be copied }

4 Title($title); <form><table> <tr><td> echo($msg); </td></tr> <tr><td>Title</td> <td><input name="Data[Title]" type="text"

value=" if(($form=="Edit")||($form=="copy")) echo $result['Title'];"></td></tr> If($form==”Edit”){ // retrieve data, show link to container, if exists… } elseif ($form==”createInsideContainer”){ //show link to container }

5 foreach($attributes as $attribute) <tr><td>echo $attribute; </td> <td><input name="Data[echo $attribute;]" type="echo ($module_name=="File" && $attribute=="FileUpload")? "file":"text";" value="if(($form=="Edit")||($form=="copy")) echo $result[$attribute];" > </td></tr> }

6 If($form==”Edit”){ <tr><td>Change Remark</td> <td><textarea name="Remark" ></textarea></td></tr> } <input type="hidden" name="cmd" value="$nextAction"> }

Code with productCode with product--specific variants specific variants


What else can we do to easier What else can we do to easier

manage product variants?manage product variants?

19


Do domain analysisDo domain analysisanalysis of requirements for many PCEs

each PCE involves entities and operations

PCE modules implement operations for entities

entities:

operations:

Staff Project Product

Create Edit Delete Display Save


Set up product architectureSet up product architecturefirst step towards systematic reuse: – set up product architecture shared by all product variants

(software Product Line architecture)

– some feature can be mapped into components

variant features

DigGemDigGem

HuntHunt

JumpJump

FeedingFeeding

reusable componentsvariant features

PCEPCE--11

PCEPCE--22

PCEPCE--33

PCEPCE--44

PCE

development

reusable components

20


Modules for Staff, Project, Modules for Staff, Project, ……


Similarity/difference analysisSimilarity/difference analysisunderstand the exact similarities and differences among PCE

Operations Create for Staff, Project, Product, etc. are similar but also different

entities:

operations:

Staff Project Product

Create Edit Delete Display Save

21


Group of similar operations: Group of similar operations: Create[ECreate[E]]

CreateStaff.BLvalidateStaff()

Staff.DBaddStaff()Staff Table

Project.DBaddProject()Project Table

CreateProject.BLvalidateProject()

CreateStaff.UIcreateStaff()

CreateProject.UIcreateProject()

Product.DBaddProduct()Product Table

CreateProduct.BLvalidateProduct()

CreateProduct.UIcreateProduct()

CreateStaff CreateProject CreateProduct


Group of similar operations: Group of similar operations: EEddiitt[E[E]]

EditStaff.BLvalidateEditStaff()

Staff.DBeditStaff()Staff Table

Project.DBeditProject()Project Table

EditProject.BLvalidateEditProject()

EditStaff.UIeditStaff()

EditProject.UIeditProject()

Product.DBeditProduct()Product Table

EditProduct.BLvalidateEditProduct()

EditProduct.UIeditProduct()

EditStaff EditProject EditProduct

22


Idea: Generic PCE modulesIdea: Generic PCE modules

generic PCE modules in XVCL

Create[E].UI

Create[E].BL

Create[E].DB

Edit[E].UI

Edit[E].BL

Edit[E].DB

productdevelopment

UI for CreateStaff

BL for CreateStaff

Staff Table Project Table Product Table

BL for CreateProject

BL for CreateProduct

UI for CreateProject

UI forCreateProduct

UI for EditStaff

BL for EditStaff

Staff Table Project Table Product Table

BL for EditProject

BL for EditProduct

UI for EditProject

UI forEditProduct

UI for …

BL for …

… … …

BL for …

BL for …

UI for …

UI for…

PCE variants

Create[E].UI

Create[E].BL

Create[E].DB

Edit[E].UI

Edit[E].BL

Edit[E].DB


A simple mechanism for unrestricted generic design

Automated by XVCL Processor

Used in sync with conventional OO/component technologies:

– C, C++, Java, ASP, PHP, JEE, .NET, etc.

Public domain, available at http://xvcl.comp.nus.edu.sg

XVCL method supported by XVCL Workbench

Based on Bassett’s frames, Frame Technology™, Netron, Inc

XVCLXVCLXMLXML--based Variant Configuration Language based Variant Configuration Language

23


XVCL approach to reuse:XVCL approach to reuse:

Avoid repetitions:1. Observe similarities across product variants

similar program structures of any kind

2. Represent them in generic, adaptable form (XVCL)

We apply parameterization and generic design– in addition to component and architecture design


A glimpse at technical A glimpse at technical

underpinsunderpins

24


Unify repetitions across Unify repetitions across PCEsPCEswe observe repetitions (similarities) across PCEsS-i : similar program structures– functions, classes, files, components, component configurations,

subsystems

PCEPCE--11S-1

S-4

S-3

S-2 PCEPCE--22

PCEPCE--33

PCEPCE--44

generic PCE

S-gen

1 2 3 4

variant features


Migration into XVCLMigration into XVCL

generic S-gen represents both S-1 and S-2S-gen

PCE-PLA in XVCL

PCE-1

S-1

S-1 and S-2 are similar program structures in games PCE-1 and PCE-2

specs of how to adapt S-gen to obtain S-1 and S-2

XVCL Processor

PCE-2

S-2

25


Managing PCE variants with XVCLManaging PCE variants with XVCL

variant features

PCEPCE--

PCEPCE

PCEPCE--

members of PCE-PL

PCE-PLA in XVCL

Create[E].UI

Create[E].BL

Create[E].DB

Edit[E].UI

Edit[E].BL

Edit[E].DB

productderivation

XVCL Processor


Generic PCE with XVCLGeneric PCE with XVCL

SPC

Create [E] Edit [E]

Level 1:

Level 2:

Level 3:

others

Create[E].BL Create[E].DBCreate[E].UI Edit [E].BL Edit [E].DBEdit [E].UI

Level 4:

Level 5:

generic classes

generic methods

generic operations(patterns of component

generic operationcomponents

in SPC, we specify entities and actions we need in PCE and entity-level customizations

here we specify a component pattern for each actions and customizations for UI, BL and DB components

here we specify customizations per entity action: CreateStaff, CreateTask, EditStaff,EditTask, etc.

26


feature diagram

Buffer

Element Type(T)

Access Mode(AM)

Memory AllocationScheme (MS)

Direct

Native

View Buffer(VB)

Read-Only Writable

Non-direct

Non-nativeLittle-Endian Big-Endian

doublefloat

char

byte

short

longint

Alternativefeatures

Mandatoryfeatures

Byte Order(BO)

Optionalfeatures

specificationof custom PCEs

SPC PCE-1 SPC PCE-2 SPC PCE-3 SPC PCE-4 SPC PCE-5

generic, reusable x-frames

PCE-Module

Create [E] Edit [E] others

Create[E].BL Create[E].DBCreate[E].UI Edit [E].BL Edit [E].DBEdit [E].UI

generic classes

generic methods

generic operations(patterns of components)

generic operationcomponents

feature selection

XVCL Processor

custom PCE products

PCE-2

PCE-3

PCE-4

PCE-1


What can we achieve What can we achieve

in XVCL way?in XVCL way?

27


Web Portal in ASP/XVCLWeb Portal in ASP/XVCLby ST Electronics (Info-Software Systems) Pte Ltd

Details in : Pettersson, U., and Jarzabek, S. “Industrial Experience with Building a Web Portal Product Line using a Lightweight, Reactive Approach,” ESEC-FSE'05, European Software Engineering Conference and ACM SIGSOFTSymposium on the Foundations of Software Engineering, Sept. 2005, Lisbon, pp. 326-335


4

4XVCL-based development

ASP / XVCL WPProduct Line Architecture

From PCE to WP Product LineFrom PCE to WP Product Line

Personal Portal(home)

Conventional ASP Development

PCE

1

5

New PortalVariants

(generated)People Tracking

(business product - SARS)

2

PCE Variants(office)

3 6

REACTIVE

28


Experiences from ASP/XVCL project:Experiences from ASP/XVCL project:

STEE has built and maintains over 20 different portals – based on XVCL-enabled Product Line architecture

Short time (less than 2 weeks) and small effort (2 persons) to start seeing the benefitsHigh productivity in building new portals with XVCL– 60% - 90% reduction of code needed to build a new portal– estimated eight-fold reduction of effort

Reduced maintenance effort for released portals– for the for first nine portals, managed code lines was 22% less

than the original single portal


technology impact – benefit: balancing cons and pros– impact on maintenance – a critical factor in technology evaluation

where do we place technologies on this scale?

technology Ttechnology THLLHLLOOOOJ2EE, .NET, J2EE, .NET, ……

overhead of T:overhead of T:learning curvelearning curvecomplexitycomplexityproblems inducedproblems induced

problems solved by Tproblems solved by T

highhigh--level programming languages HLLlevel programming languages HLL((much productivity gainmuch productivity gain))

cons

pros

Impact of technology on productivityImpact of technology on productivity

29


Trade offsTrade offsXVCL applied with good results:– only in small- to medium-size projects– agile development methods

Integration with standard processes is a challenge– XVCL Workbench– technology transfer and methodological

guidelines


Other applications of XVCLOther applications of XVCLMobile phone games

Zhang, W. and Jarzabek, S. “Reuse without Compromising Performance: Experience from RPG Software

Product Line for Mobile Devices,” 9th Int. Software Product Line Conference, SPLC’05, September

2005, Rennes, France, pp. 57-69

Business financial systems– Fudan Wingsoft Ltd, used at Fudan University, Shanghai Jiaotong University,

Zhejiang University, Harbin Institute of Technology, Sichuan University, and

Chongqing University

Java Buffer libraryJarzabek, S. and Li, S. ”Unifying clones with a generative programming technique: a case study,”

Journal of Software Maintenance and Evolution: Research and Practice, July/August 2006,

pp. 267-292, also ESEC-FSE’03 paper that received ACM Distinguished Paper Award

30


ReferencesReferencesXVCL, XML-based Variant Configuration Language, xvcl.comp.nus.edu.sgJarzabek, S. Effective Software Maintenance and Evolution: Reused-based Approach,

Auerbach, CRC Press Taylor and Francis, May 2007Patterson, U., and Jarzabek, S. “Industrial Experience with Building a Web Portal Product Line

using a Lightweight, Reactive Approach,” ESEC-FSE'05, European Software Engineering Conference and ACM SIGSOFT Symposium on the Foundations of Software Engineering, ACM Press, September 2005, Lisbon, pp. 326-335

Zhang, W. and Jarzabek, S. “Reuse without Compromising Performance: Experience from RPG Software Product Line for Mobile Devices,” 9th Int. Software Product Line Conference, SPLC’05, September 2005, Rennes, France, pp. 57-69

Yang, J. and Jarzabek, S. “Applying a Generative Technique for Enhanced Reuse on J2EE Platform,” 4th Int. Conf. on Generative Programming and Component Engineering,GPCE'05, Sep 29 - Oct 1, 2005, Tallinn, Estonia, pp. 237-255

Basit, H. A., Jarzabek, S. “Data Mining Approach for Detecting Higher-level Clones in Software,” to appear in IEEE Trans. on Soft. Eng.

Yali Zhang, Hamid Abdul Basit, Stan Jarzabek, Dang Anh, and Melvin Low “Query-based Filtering and Graphical View Generation for Clone Analysis,” Proc. 24th IEEE Int. Conf. on Software Maintenance, ICSM’08, Beijing, September 2008, pp. 376-385


Q & AQ & A

31


Mobile phone softwareMobile phone softwareapplied to manage RPG product variantsreuse without compromising performance

Zhang, W. and Jarzabek, S. “Reuse without Compromising Performance: Experience from RPG Software Product Line for Mobile Devices,” 9th Int. Software Product Line Conference, SPLC’05, September 2005, Rennes, France, pp. 57-69


Financial softwareFinancial softwaredeveloped by Fudan Wingsoft Ltd

product variants used at over 80 institutions– Fudan University, Shanghai Jiaotong University,

Zhejiang University, Harbin Institute of Technology, Sichuan University, and Chongqing University

all-in-one product– conditional compilation, comments, config files, Ant

migrated to XVCL

32


Buffer library, JDK 1.5Buffer library, JDK 1.5

Jarzabek, S. and Li, S. ”Unifying clones with a generative programming technique: a case study,”Journal of Software Maintenance and Evolution: Research and Practice, July/August 2006, pp. 267-292, also ESEC-FSE’03 paper that received ACM Distinguished Paper Award


Java/XVCL vs. original classesJava/XVCL vs. original classes

LOC reduction: 68% Java code, 72% (code + comments)in Java/XVCL, we count both Java code and XVCL commands

LOCLOC

0

2000

4000

6000

8000

10000

12000

14000

Java code Java code with comments

Java/XVCLJava/XVCL original classesoriginal classes

33


Migration product variants Migration product variants

to XVCLto XVCL

Similarity analysis of product variantsSimilarity analysis of product variants


Migration products to XVCLMigration products to XVCL1. Understand commonalities and differences among PCEs

2. Set up component architecture for PCEs

3. Build generic XVCL structures for groups of similar software structures in PCE

4. Derive PCEs from generic PCE in XVCLDigGem

Hunt

Jump

Feeding

PL members

XVCL-PLA

productderivation

XVCL Processor

34


Clone Miner and AnalyzerClone Miner and AnalyzerClone Miner (CM) detects similar program structures:

first, CM detects simple clones – a token based clone detector, similar to CCFindernext, CM applies data mining techniques to find configurations of simple clones as candidates for structural clones

Clone Analyzer (CA)helps find meaningful clones

– graphical presentations of similarity situation, queries---------------------------------------------------------------------Clone Miner: Basit, A.H. and Jarzabek, S. “Detecting Higher-level Similarity Patterns in

Programs,” ESEC-FSE'05, September 2005, Lisbon, pp. 156-165; ICSM,08, CM/CA technology summary


Find and analyze similaritiesFind and analyze similarities

Clone Miner (CM):find similar code fragments first (simple clones)find recurring simple clone patterns raise level of clone detection, iterate

Clone Analyzer (CA)query-based filtering, visualization

35


Clone MinerClone Miner

CMCM++

Domain analysisDomain analysislegacy PCElegacy PCE

CreateStaff.BLvalidateStaff()

Staff.DBaddStaff()Staff Table

Project.DBaddProject()Project Table

CreateProject.BLvalidateProject()

CreateStaff.UIcreateStaff()

CreateProject.UIcreateProject()

Product.DBaddProduct()Product Table

CreateProduct.BLvalidateProduct()

CreateProduct.UIcreateProduct()



Legacy systemSimple clones in files Locate recurring patterns of clones

1

9876

5432

1312 14

10

11 15

1,4,8,10,11,12

1,4,7,8,10,11,12

2,5,9,13,15

source code filessource code files

36



1

8

11 10

12

4

7 13 5

9 15

2

Domain AnalysisSimilarity abstraction: identify similar files

Create Entity Form files

Entity Business

Logic files

Identify collaborations



High Level Similarity Pattern

1 104 8 7

151392 5

XVCL Representationcreate project form

create staff form

create task form

Project logic

Task logic

Staff Logic

create [X]

form

[X] logic

37


Clone Analyzer: Clone Analyzer: comparing clonescomparing clones

73

74ICSE’09 Tutorial 24 Copyright (C) 2009 Stan Jarzabek 74

Clone Analyzer: Clone Analyzer: visualizing similaritiesvisualizing similarities

38


XRF XRF –– migration facilitymigration facilitya Workbench for migrating products to XVCL


Toy example: similar Account classesToy example: similar Account classes

class SavingsAccount {public static void main(String[] args) {

System.out.println(“This is a bank account”);System.out.println(“Savings Account”);

}}

class CurrentAccount {public static void main(String[] args) {

System.out.println(“This is a bank account”);System.out.println(“Current Account”);

}}

class LoanAccount {public static void main(String[] args) {

System.out.println(“This is a bank account”);System.out.println(“Loan Account”);

}}

39


x-frame Accountclass @className {

public static void main(String[] args) {<while messages>

System.out.println(“@messages”);</while>}

}

class SavingsAccount {public static void main(String[] args) {

System.out.println(“This is a bank account”);System.out.println(“Savings Account”);

}}

x-frame SPC<set className = SavingsAccount /><set messages = This is a bank account, Savings Account/><adapt Account />

XVCL Processor

Savings

Loan

Current

Generic class AccountGeneric class Account


Deriving Current AccountDeriving Current Account




}



}}

x-frame SPC<set className = CurrentAccount /><set messages = This is a bank account, Current Account/><adapt Account />

XVCL Processor

40


Deriving three Account classesDeriving three Account classesclass SavingsAccount {

public static void main(String[] args) {System.out.println(“This is a bank account”);System.out.println(“Savings Account”);

}}

x-frame SPC<set className = SavingsAccount, CurrentAccount,

LoanAccount /><set common = This is a bank account/><while className>

<select option = className><option SavingsAccount >

<set messages = @common, Savings Account /><adapt Account />

<option CurrentAccount ><set messages = @common, Current Account /><adapt Account />

<option LoanAccount ><set messages = @common, Loan Account /><adapt Account />

</select></while>



}}

class LoanAccount {public static void main(String[] args) {

System.out.println(“This is a bank account”);System.out.println(“Loan Account”);

}}




}

XVCL Processor


<adapt><adapt>--driven composition of xdriven composition of x--framesframes

SPC

Saving.s

Account

Current.s

Start

XVCL Processor

processing path

generated classes

End ! SavingAccount {

…

}

CurrentAccount {

…

}

other

LoanAccount {

…

}

how does this compare to generics/templates so far?

41


XVCL Processor operationXVCL Processor operation<adapt> command instructs the processor to:

1. process the specified x-frame and all x-frames adapted from there

2. perform customizations of all the adapted x-frames as specified in <adapt> body

3. interpret any XVCL commands embedded in visited x-frames

4. emit the result to the specified output file


Evolution of classesEvolution of classes

42


Foreign currency accountForeign currency accountwe need class FcAccount for foreign currencyclass FcAccount needs some extra methods as compared to other account classes

class FcAccount {public static void main(String[] args) {

System.out.println(“This is a bank account”);System.out.println(“Foreign Account”);

}// extra methods for FcAccount

int convert () { … }int interest () { … }

}




System.out.println(“@messages”);</while>

}<break extra-methods>}

class SavingsAccount {}

x-frame SPC<set className = SavingsAccount, CurrentAccount, LoanAccount, FcAccount /><set common = This is a bank account/><while className>

<select option = className><option SavingsAccount >

<set messages = @common, Savings Account /><adapt Account />

<option CurrentAccount ><set messages = @common, Current Account /><adapt Account />

<option LoanAccount ><set messages = @common, Loan Account /><adapt Account />

<option FcAccount ><set messages = @common, Foreign Account /><adapt Account >

<insert extra-methods>// extra methods for Foreign Account:

int convert () { … } int interest () { … }

</insert></select>

</while>

XVCL Processor

class LoanAccount {}

class CurrentAccount {}

class FcAccount {public static void main(String[] args) {

System.out.println(“This is a bank account”);System.out.println(“Foreign Account”);

}// extra methods for Foreign Account:

int convert () { … } int interest () { … }

}

43


x-frame SPC<set v = X /><set Type = Byte, Char, Double, Float, Int, Long, Short /><adapt A><adapt B>

<insert b>code spc

</adapt>

x-frame A<while Type>

class @TypeBuffer {<select option = elmntType >

<option Byte> @Type b;

<option Char>@Type c;

</select></while>

x-frame B<set v = Y />

reference to v: @v

<adapt C>

<insert b>code bbbb

</adapt>

x-frame C

<break b>

code cccc

</break>

adapts

how does this compare to generics/templates?


Q & AQ & A

--- The End ---

Documents

Problems we can Solve with Power-Generics Tut24 power... · Title: Microsoft PowerPoint - ICSE09 Tut24 power-generics StanJ 3April09 Author: dcssj Created Date: 4/8/2009 3:38:02 PM