IECI Chapter Japan Series Vol. 3 No. 1, 2001 ISSN

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1 IECI Chaper Japan Series Vol. 3 No. 1, 2001 ISSN Proceedings of he IECI Japan Workshop 2001 IJW-2000 Suppored by Indonesian Sociey on Elecrical, Elecronics, Communicaion and Informaion IECI Indonesian Sudens Associaion PPI Insiue for Science and Technology Sudies ISTECS Organized by Indonesian Sociey on Elecrical, Elecronics, Communicaion and Informaion IECI Japan In Cooperaion Wih The Universiy of Tokyo

2 Objec Based Formal Specificaion: Mehodological Suppor for Specifying Requiremens in Objec Model Creaion Process Romi Saria Wahono and Behrouz H. Far Deparmen of Informaion and Compuer Sciences, Graduae School of Science and Engineering, Saiama Universiy Absrac: Requiremen acquisiion is considered as one of he mos imporan aciviies in sofware developmen. Mos fauls found during esing and operaion resul from poor undersanding or misinerpreaion of requiremens. We propose an approach where end users ake an acive role in analysis by specifying requiremens using Objec Based Formal Specificaion OBFS. We use OBFS o guide end users in describing heir problem. This approach is a firs imporan sep for solving he difficulies and ill-defined asks in he objec model creaion process. In his paper we presen OBFS and is roles o be mehodological suppor for specifying requiremens in objec model creaion process, including idenificaion process and objec refinemen wih inheriance process. Keywords: Requiremen Engineering, Objec Model Creaion Process, Objec-Oriened Analysis and Design 1. INTRODUCTION Requiremen acquisiion is considered as one of he mos imporan aciviies in sofware developmen. Mos fauls found during esing and operaion resul from poor undersanding or misinerpreaion of requiremens. In spie of progress in analysis echniques, Compuer Aided Sofware Engineering CASE ools suppor, prooyping, early verificaion and validaion. Sofware developmen sill suffers from poor requiremens acquisiion. In he radiional approach o sofware analysis, sysem analys inerviews end users o capure requiremens. We propose an approach where end users ake an acive role in analysis by specifying requiremens using Objec Based Formal Specificaion OBFS. We use OBFS o guide end users o describe heir problem. This approach will be a firs imporan sep for solving he difficulies and ill-defined asks in he objec model creaion process, including idenificaion of objecs, relaionships, aribues, behaviors and organizaion of objecs wih inheriance. This approach also akes advanage of end users domain knowledge. In his paper we presen OBFS and is roles o be a mehodological suppor for specifying requiremens in objec model creaion process, including idenificaion process objec idenificaion, associaion idenificaion, aribue idenificaion, behavior idenificaion, and objec refinemen wih inheriance process. 2. OBJECT BASED FORMAL SPECIFICATION and ITS MODEL Figure 1 shows our sraegy o formulae requiremen specificaion for solving he objec model creaion process. We propose an approach where end users ake an acive role in analysis by specifying requiremens using OBFS. We use OBFS o guide end users in describing heir problem. OBFS is composed of Descripion Saemens DS, Collaboraive Saemens CS, Aribuive Saemens AS, Behavioral Saemens BS, and Inheriance Saemens IS. OBFS = DS CS AS BS IS Each OBFS saemen consiss of Subjec S, Verb V, and Objec O as well as he English E naural DS = CS = AS = BS = IS = { reqid, reqname, Language, Descripion} { S1, V1, O1 cs, S2, V2, O2 cs, S3, V3, O,...} and 3 cs { S1, V1, O1 as, S2, V2, O2 as, S3, V3, O3 as,...} { S1, V1, O1 bs, S2, V2, O2 bs, S3, V3, O3 bs,...} { S, V, O, S, V, O, S, V, O,...} is is OBFS E is Regular Paper 57 IECI Chaper Japan Series Vol. 3 No. 1, 2001

3 OBFS Idenifying Problem Domain A Unique ID of he Requiremen A Tile of he Requiremen Language used in he Requiremen Collaboraive Saemens Idenifying Objecs and Associaions Aribuive Saemens Descripion Saemens Idenifying Aribues Behavioral Saemens Idenifying Behaviors The problem saemens of he inenion of he requiremen Inheriance Saemens Refining Wih Inheriance Class Model Figure 1: Objec Based Formal Specificaion OBFS Definiion 2.1 Objec-Based Formal Specificaion OBFS: Objec-Based Formal Specificaion OBFS is a semi-formal requiremens emplae used o reveal ambiguiy, incompleeness, and inconsisency in an objec-oriened sofware sysem, and o guide end users ake an acive role while describing heir problem saemens. OBFS is composed of descripion saemens DS, collaboraive saemens CS, aribuive saemens AS, behavioral saemens BS, and inheriance saemens IS Descripion Saemens DS Descripion Saemens DS are used o guide wriing an overview of he sysem ha we wan o build. DS conain four kinds of elemens: Requiremen ID, Requiremen Name, Language, and Descripion Figure 2. The descripion saemens should sae wha is o be done and no how i is o be done. I should be a saemen of needs, no a proposal for a soluion. Figure 2: Descripion Saemens Shell Definiion 2.2 Descripion Saemens DS: A descripion saemen is an OBFS saemen used o wrie an overview of he sysem ha we wan o build, which consiss of Requiremen ID, Requiremen Name, Language, and Descripion Collaboraive Saemens CS Collaboraive saemens CS are used o idenify objecs, and associaion beween objecs. The firs sep in objec model creaion process is o idenify relevan objecs and is associaions wih he applicaion domain. Objecs include physical eniies and all objecs mus make sense in he applicaion domain. All objecs are explici in he CS, and objecs are corresponding o nouns ha are idenified from collaboraive saemens. Any dependency beween wo or more objecs in he CS is an objec associaion. A reference from one objec o anoher is also an associaion. Associaions show dependencies beween objecs a he same level of absracion as he objecs hemselves. Associaions can be implemened in various ways, bu such implemenaion decisions should be kep ou of he analysis model o preserve design freedom. Associaions ofen correspond o verbs or verb phrases. CS consiss of Subjec S, Verb V, and Objec O as well as he English E naural Regular Paper 58 IECI Chaper Japan Series Vol. 3 No. 1, 2001

4 { S, V, O, S, V, O, S, V, O,...} CS = and cs cs cs CS E S cs and O cs will be idenified as a enaive objec OBJ, and V cs will be idenified as a enaive associaion ASS in erms of objec-oriened paradigm. CS E S cs OBJ ] and CS E O cs OBJ ] CS E V cs ASS ] Definiion 2.3 Collaboraive Saemens CS: A collaboraive saemen is an OBFS saemen, which has a uple {S cs,v cs, O cs }. An Objec OBJ is derived from S cs and O cs, and associaion beween objec ATT is derived from V cs Aribuive Saemens AS Aribuive saemens AS are used o idenify objec aribues. Aribues are properies of individual objecs. Aribues usually correspond o nouns followed by possessive phrases, and someimes are characerized by adjecives or adverbs. AS mus conain properies of each objec idenified a he previous sep. AS consiss of Subjec S, Verb V, and Objec O as well as he English E naural { S, V, O, S, V, O, S, V, O,...} AS = and as as as AS E O as will be idenified as a enaive aribue ATT in he erm of objec-oriened paradigm. And S as is idenified and refined objecs OBJ from enaive objec OBJ, as he final resul of objec idenificaion s process. AS E O as ATT ] AS E S = as OBJ ] Definiion 2.4 Aribuive Saemens AS: An aribuive saemen is an OBFS saemen, which has a uple {S as,v as, O as }. S as is an idenified objec OBJ, and V as is a consan word, which shows ha O as is an aribue of S as. The objec s aribue ATT is derived from O as Behavioral Saemens BS Behavioral saemens BS are used o idenify objec behaviors. Behavior is how an objec acs and reacs, in erms of is sae changes and message passing Booch, 1991]. BS conain behaviors of each objec idenified a he previous sep. BS consiss of Subjec S, Verb V, and Objec O as well as he English E naural BS = { S, V, O, S, V, O, S, V, O,...} bs bs bs and BS E O as will be idenified as a enaive behavior BEH in he erm of objec-oriened paradigm. And S bs is idenified and refined objecs OBJ from enaive objec OBJ, as he final resul of objec idenificaion s process. BS E O bs BEH ] BS E S = bs OBJ ] Definiion 2.5 Behavioral Saemens BS: An behavioral saemen is an OBFS saemen, which has a uple {S bs,v bs, O bs }. S bs is an idenified objec OBJ, and V bs is a consan word, which shows ha O bs is a behavior of S bs. The objec s behavior BEH is derived from O bs Inheriance Saemens IS Inheriance saemens IS are used o organize classes by using inheriance, o share common objec aribues and behaviors. Inheriance provides a naural classificaion for kinds of objecs and allows for he commonaliy of objecs o be explicily aken advanage of in modeling and consrucing objec sysems. Inheriance is a relaionship beween classes where one class is he paren class of anoher. IS provides senences ha have is-a-kind-of relaionship. Inheriance can be added in wo direcions, boom up generalizaion and op down specializaion. Boom Up Generalizaion: By generalizing common aspecs of exising classes ino a superclass. We can discover inheriance from he boom up by searching Regular Paper 59 IECI Chaper Japan Series Vol. 3 No. 1, 2001

5 for classes wih similar aribues, associaions, or behaviors. Top Down Specializaion: By refining exising classes ino specialized subclass. Definiion 2.6 Generalizaion and Specializaion: Generalizaion and Specializaion are relaionships beween conceps. Any ype of A, each of whose objecs is also an insance of a given ype B, is called a specializaion or subype of B and is wrien as A B. B is also called he generalizaion or superype of A. However, mainly we use boom-up generalizaion conceps as a basic approach o build IS. IS consiss of Subjec S, Verb V, and Objec O as well as he English E naural IS = { S, V, O, S, V, O, S, V, O,...} and is is is IS E O is will be idenified as a enaive superclass SCL in he erm of objec-oriened paradigm. And S is is idenified and refined objecs OBJ from enaive objec OBJ, as he final resul of objec idenificaion s process. IS E O is SCL ] Each agen is an inelligen in is own field and may inerac wih is human counerpar or behave auonomously. This sysem is named OOExper Romi e al, June 1999] Romi e al., July 2000]. Requiremens acquisiion agen manages he ask concerning he requiremens acquisiion from OBFS. Objec idenificaion agen manages he ask concerning he objec idenificaion. Aribue idenificaion agen manages he ask concerning he idenificaion of objec aribues. Associaion idenificaion agen manages he ask concerning he idenificaion of associaions beween he idenified objecs. Behavior idenificaion agen manages he ask concerning he idenificaion of objec behaviors. Objec refinemen agen manages he ask concerning o refine objecs and organize classes by using inheriance o share common srucure Requiremen Specificaion Requiremen Acquisiion - Send OI reques - Send AI reques Objec Idenificaion - Send OR reques Class Model IS E S = is OBJ ] -Send BI reques -Send AIreques Associaion Idenificaion Definiion 2.7 Inheriance Saemens IS: An Inheriance saemen is an OBFS saemen, which has a uple {S is,v is, O is }. S is is an idenified objec OBJ, and V is is a consan word, which shows ha O is is a superclass of S is. The subclass CLS is derived from S is, and he superclass SCL is derived from O is. 3. IMPLEMENTATION In his research, objec model creaion process is viewed as a sociey of sofware agens ha inerac and negoiae wih each oher. We have devised six ypes of agens: requiremen acquisiion agen, objec idenificaion agen, aribue idenificaion agen, associaion idenificaion agen, behavior idenificaion agen, and objec refinemen agen Figure 3. Behavior Idenificaion Aribue Idenificaion -Send OR reques Figure 3: OOExper s Objec Refinemen 4. CONCLUSION We propose an approach where end users ake an acive role in analysis by specifying requiremens using Objec Based Formal Specificaion OBFS. In his paper we presen OBFS and is roles o be a mehodological suppor for specifying requiremens in objec model creaion process, including idenificaion process and objec refinemen wih inheriance process. The models and implemenaion for using OBFS are also presened. Regular Paper 60 IECI Chaper Japan Series Vol. 3 No. 1, 2001

6 5. REFERENCES Booch, 1991] Grady Booch, "Objec-Oriened Analysis and Design wih Applicaion", Benjamin/Cummings, Booch e al., 1999] Grady Booch, James Rumbaugh, and Ivar Jacobson, "The Unified Modeling Language User Guide", Addison-Wesley, Holland e al., 1996] Ian M. Holland and Karl J. Lieberherr, "Objec-Oriened Design", ACM Compuing Surveys, Vol. 28, No. 1, March Liang e al., 1998] Ying Liang, Daune Wes, and Frank A. Sowell, "An Approach o Objec Idenificaion, Selecion and Specificaion in Objec-Oriened Analysis", Informaion Sysems Journal, Vol. 8, No. 2, 1998, pp , Blackwell Science Ld., Romi e al, June 1999] Romi Saria Wahono and B.H. Far, "OOExper: Disribued Exper Sysem for Auomaic Objec-Oriened Sofware Design", Proceedings of he 13h Annual Conference of Japanese Sociey for Arificial Inelligence, pp , Tokyo, Japan, June Romi e al., July 2000] Romi Saria Wahono and Behrouz H. Far, "Hybrid Reasoning Archiecure for Solving Objec Class Idenificaion Problem in he OOExper Sysem", Proceedings of he 14h Annual Conference of Japanese Sociey for Arificial Inelligence, Tokyo, Japan, July, Rumbaugh e al., 1991] James Rumbaugh, Michael Blaha, William Premerlani, Frederick Eddy, and William Lorenson, "Objec-Oriened Modeling and Design," Prenice Hall, Rumbaugh e al., 1999] James Rumbaugh, Ivar Jacobson, and Grady Booch, "The Unified Modeling Language Reference Manual", Addison-Wesley, BIOGRAPHY of AUTHOR Romi Saria Wahono, Received B.Eng. and M.Eng degrees in Informaion and Compuer Sciences in 1999 and 2001, respecively, from Saiama Universiy. He is currenly a researcher a he Indonesian Insiue of Sciences LIPI, and a Ph.D. candidae a he Deparmen of Informaion and Compuer Sciences, Saiama Universiy. The research fields of his ineress are Muli Sysems, Reasoning Sysem, Sofware Engineering, and Objec-Orienaion. He is a member of he ACM, IEEE Compuer Sociey, The Insiue of Elecronics, Informaion and Communicaion Engineers IEICE, Japanese Sociey for Arificial Inelligence JSAI, and Indonesian Sociey on Elecrical, Elecronics, Communicaion and Informaion IECI. Behrouz Homayoun Far, Received BSc. and MSc. degrees in Elecronic Engineering in 1983 and 1986, respecively, from Tehran Universiy, Iran. He has received his Ph.D. degree from Chiba Universiy - Japan, in He is currenly an Associae Professor a he Deparmen of Informaion and Compuer Sciences, Saiama Universiy - Japan. The research fields of his ineres are qualiaive reasoning, auomaic programming and disribued AI. Dr. Far is a member of he ACM, IEEE Compuer sociey, Japanese Sociey for Arificial Inelligence, IEICE and Informaion Processing Sociey of Japan. Regular Paper 61 IECI Chaper Japan Series Vol. 3 No. 1, 2001