Exploiting Contextual Information to Understand Object-Oriented Systems

130 Pages·2006·2.16 MB·English

by  Laura Ponisio

Exploiting Client Usage to Manage Program Modularity
Inauguraldissertation
derPhilosophisch-naturwissenschaftlichenFakulta¨t
derUniversita¨tBern
vorgelegtvon
Mar´ıa Laura Ponisio
vonArgentinien
LeiterderArbeit:
Prof.Dr.OscarNierstrasz
Prof.Dr.Ste´phaneDucasse
Institutfu¨rInformatikundangewandteMathematik

Exploiting Client Usage to Manage Program Modularity
Inauguraldissertation
derPhilosophisch-naturwissenschaftlichenFakulta¨t
derUniversita¨tBern
vorgelegtvon
Mar´ıa Laura Ponisio
vonArgentinien
LeiterderArbeit:
Prof.Dr.OscarNierstrasz
Prof.Dr.Ste´phaneDucasse
Institutfu¨rInformatikundangewandteMathematik
VonderPhilosophisch-naturwissenschaftlichenFakulta¨tangenommen.
Bern,30.06.2006 DerDekan:
Prof. P.Messerli

Abstract
Over the last thirty years designers have tried to cope with software complexity by orga-
nizing system entities into modules, i.e., groups of entities. However, the creation and
organization of modules is not straightforward. The criterion with which these modules
are built impacts in the maintainability and development of the system. Designers have
different interests and personal views of the same system, views that are difficult to
communicate and to extract from the code. Poor understanding of this organization in-
creases the complexity of the system e.g., by favoring the addition of duplication and of
unexpectedripplingeffects. This,inturn,lowerstheflexibilityofthesystemtochanging
requirements and leads to a sharp increase in their maintenance cost.
Toovercometheseproblems,wepresentamethodologytomanagethelocalityinobject-
oriented systems. We develop a model that exploits the contextual information, i.e.,
the way objects are used by their clients, to understand and improve the organization
of classes in the system. With our model we take full advantage of the contextual
information of modules to evaluate their cohesion, find misplaced classes, detect hot
spots and find the different views that its clients have.
In our experimental validation we apply the contextual information to understand,
maintain and describe systems. Our methodology is applied successively together with
metrics, visualization techniques, and an optimization method named simulated an-
nealingtoreverse-engineerobject-orientedsystems. Allinall,weprovideamethodology
to understand and improve the modularization of object-oriented systems, in an effort
towards simplicity.

To my parents Mar´ıa Cristina Noval
and Jorge Roberto Ponisio
To my grandparents Cristina Torrente,
Emilio Higinio Noval,
Ange´lica Emma Ep´ıscopo,
and Domingo Angel Ponisio

Acknowledgments
Firstandforemost, IwouldliketoexpressmygratitudetoProf. OscarNierstraszforhis
guidance, encouragement and for being always there when I needed him. Oscar, it was
a pleasure working with you.
IwouldliketothanktoProf. Ste´phaneDucasseforthelongdiscussions,energy,interest
in my work and for letting me share unforgettable moments with his family.
I am grateful also to Prof. Houari Sahraoui for generously giving me ideas, for his pa-
tience,foracceptingtoreviewmythesis,andforcomingovertomyPh. D.defense.
Many thanks to Prof. Hanspeter Bieri for his warm welcome in the university of Bern
and for accepting to chair the defense.
Veryspecialthanksgotomyfamily. Ithankmyparents,Mar´ıaCristinaNovalandJorge
Roberto Ponisio, my grandparents Cristina Torrente, Emilio Higinio Noval, Ange´lica
EmmaEp´ıscopo,andDomingoAngelPonisio,andmyaunt,uncleandcousinAnaMar´ıa
Noval, Alejandro Azadte and Paula Prieto for their terrific support, encouragement and
love.
I would also like to thank my friends for sharing their life with me. Thanks to Luis
Cleve and Stella Co´rdoba for their unconditional advice and support. Special thanks
to Lelli Samanta, Marcel Zumbu¨hl, Gian Luca Zumbu¨hl for making me feel part of the
family. Many thanks to Andreas Schlapbach for helping me, for his company and for
the many interesting lunches together. Many thanks also to Therese Schmid, for her
unconditionalhelp,generosity,understanding,patience,openmind,wiseadvice,smile,
and for teaching me swiss german.
Thanks to Mart´ın Ricardo Miguel Auriemma, Mart´ın Mantovani, and Christine Violeau
for keeping the friendship despite the geographic distance.
Very special thanks to my neighbor, Gertrude Kummer, who during these three years
took care of me as a grandmother would. She called in with warm dishes in winter and
withflowersinspring. Finally,shepatientlytaughtmeGermanthroughmysensesand
through my heart.
Many thanks to all the professors who have helped me during my thesis. I especially
thank Prof. Gustavo Rossi, my mentor and advisor in the licentiate thesis in Argentina,
for believing in me and for introducing me to the world of research. Many thanks
to my advisor in the master thesis in France, Prof. Jacques Noye´ for the valuable
discussions. IthankProf. LindaOttfordiscussingsomeideaswithmeandforgivingme
advice and feedback about my work. Thanks also to Prof. Rolf Ha¨nni for the interesting
talks. Thanks to Paul Asman, who have helped me and collaborated with me during my
work.
Many thanks also to Orla Greevy, Tudor Girba and Oana Girba for reviewing my thesis
and for their comments.
Next I would like to thank all the former and current members of the Software Compo-
sition Group. It was a pleasure to work with you: Juan Carlos Cruz, Marcus Denker,
Markus Ga¨lli, Lukas Renggli, Marc-Philippe Horvath, Adrian Kuhn, Adrian Lienhard,
Alexandre Bergel, Frank Buchli, Roel Wuyts, Juan Carlos Cruz, Mauricio Seeberger,
Daniele Talerico, David Vogel, Niklaus Haldimann, Christoph Hofer, Philippe Marschall,
Gabriela Are´valo, Florian Thalmann, and Pascal Zumkehr, Matthias Rieger, Michele
Lanza, and Nathanael Scha¨rli.
Finally, I would like to send my best to all the great people I have met and talked to at
conferences, meetings, and workshops.
Usually, people ask me if it was worth it to enlarge the scenario and find my way in
Switzerland. My answer is yes; I am very happy of every single step, because it led me
to meet these people.
June30,2006
Mar´ıaLauraPonisio