1. Modular Software Development for Dealing with Uncertainty
6th Asian Workshop of Advanced Software Engineering (AWASE2017)
Modular Software Development for Dealing with Uncertainty
Naoyasu Ubayashi
Kyushu University, Japan
May 5, 2017

2. Naoyasu Ubayashi Professor @ Kyushu University Research Interests
Ph.D (University of Tokyo, 1999)
Toshiba ( ), Kyushu Tech. ( ), Kyushu U. (2010-)
POSL (Principles of Software Languages) Research Group
Research Interests
Software & Programming Languages (especially, Modularity)
Abstraction-Aware Verifying Compiler
Extensible Modelling Language
Modularity for Uncertainty
Software Repository Mining
Formal Methods

3. Outline Motivation What is Uncertainty? Modularity for Uncertainty
iArch-U: IDE for Uncertainty-Aware Software Development
Summary and Ongoing Work

4. Open Source Software
(GitHub)

5. Motivation

6. Uncertainty in Software Development
Requirements or design models tend to contain uncertainty, because all of the concerns cannot be captured at the early phase.
Uncertainty can appear in all aspects of software development.
Unfixed Requirements
Alternative Implementation Policies
Uncertain
Performance
Modelling
Programming
Testing

7. Myth in Software Engineering
Software Engineering is founded on a computational myth that no longer fully serves its purpose: that
the computational environment is predictable and in principle fully specifiable, and that
the systems that compute in those environments can in principle be engineered so that they are trouble-free.
D. Garlan: Software Engineering in an Uncertain World, FSE/SDP Workshop on Future of Software Engineering Research, 2010.

8. Uncertainty in OSS Projects
SZZ-based

9. What is Uncertainty?

10. Known Unknowns vs. Unknown Unknowns
Known what is unknown
Unknown what is unknown
e.g., Design Alternatives
Design A
Design B
Which should be selected？
e.g., Users’ Preference
Unknown Unknowns
recommend
Accepted
Unaccepted
Users
Sebastian, E., and David S. R.: Known Unknowns: Testing in the Presence of Uncertainty, 22nd ACM SIGSOFT International Symposium on Foundations of Software Engineering(FSE 2014), 2014.

11. Definition of Uncertainty
The most used definitions of uncertainty simply distinguish between natural variability of physical processes (i.e., aleatory or stochastic uncertainty) and the uncertainties in knowledge of these processes (i.e., epistemic or state-of-knowledge uncertainty).
For proposing such a taxonomy for uncertainties in computer systems models, we base on a general definition of uncertainty in modeling given in [2] as: "any deviation from the unachievable ideal of completely deterministic knowledge of the relevant system".
[1] Diego Perez-Palacin, Raffaela Mirandola: Uncertainties in the modeling of self-adaptive systems: a taxonomy and an example of availability evaluation, ICPE 2014.
[2] W. Walker, P. Harremo´ Ss, J. Romans, J. van der Sluus, M. van Asselt, P. Janssen, and M. Krauss: Defining uncertainty. a conceptual basis for uncertainty management in model-based decision support, Integrated Assessment, 4(1):5–17, 2003.

12. Uncertainty in OSS Projects
SZZ-based

13. Living with Uncertainty
Modularity
for
Uncertainty
Living with Uncertainty

14. Modular Software Development with Uncertainty
Idea 1: Uncertainty as Pluggable Interface [Expression of Uncertainty (Known Unknowns, Epistemic)]
Idea 2: Interface-Centric Modular Reasoning [Type Checking / Model Checking for Uncertainty]
Modularity for Uncertainty
Uncertain
Concerns
Uncertain
Concerns
Uncertain
Concerns
Modelling
Programming
Testing
Fukamachi, T., Ubayashi, N., Hosoai, S., and Kamei, Y., Modularity for Uncertainty, In Proceedings of the 7th International Workshop on Modelling in Software Engineering (MiSE 2015), pp.7-12, 2015.

15. Archface-U : Component Interface
Idea 1
Archface-U : Component Interface
Java Interface
interface uncertain uSubject extends Subject {
　public void {removeObserver(), deleteObserver()};
[public void notify();] }
interface component Subject {
public void addObserver();
public void setState();
Certain Archface
Uncertain Archface
{ } Alternative
[ ] Optional
Variability model is applied to uncertainty management.
(not product but process)

16. Archface-U : Connector Interface
Idea 1
Archface-U : Connector Interface
Finite State Process (FSP)
interface connector uObserverPattern extends cObserverPattern
(cSubject, cObserver) {
cSubject = (cSubject.setState-> [uSubject.notify] ->cObserver.update->cSubject.getState->cSubject); }
interface connector cObserverPattern(cSubject, cObserver) {
cSubject = (cSubject.setState->cObserver.update
->cSubject.getState->cSubject);
Certain Archface
Uncertain Archface
Magee, J. and Kramer, J.: State Models and Java Programs (1999).

17. Interface-Centric Modular Reasoning
Idea 2
Interface-Centric Modular Reasoning
We can continue development embracing uncertainty
If True…
Add
Add
Remove
Certain
Interface
Uncertain
Concerns
Uncertain
Concerns
Uncertain
Concerns
Archface-U
Test
Execution
Model
Checking
Model
Checking
Type
Checking
(Simulation)
Type
Checking
(Simulation)
True
False
True
False
True
False
Model
Code
Test
Consistency is guaranteed (via Type Checking)

18. Uncertainty-Aware Software Development
iArch-U
IDE for
Uncertainty-Aware Software Development

19. Overview of iArch-U IDE
Modeling Support
Programming Support
Testing Support
Uncertainty Management Support with Git

20. (Type Checking, Git-based Uncertainty Management)
Eclipse Plugin
Java Programming
UML Modelling
Archface-U View
(Type Checking, Git-based Uncertainty Management)
Archface-U

21. Modelling Setting of Alternative Uncertainty
Alternative Uncertainty in Sequence Diagram
Type Checking for UML Diagrams

22. Model Checking for UML Models
Modify
Archface-U
Property
Connector Interface
ERROR
Model
Checking
(LTSA)
Translate
Model OK
Type Checking
Indirectly Verified
(avoidance of state explosion)
UML Model

23. Model Checking for Java Code
Modify
Archface-U
Property
Connector Interface
ERROR
Model
Checking
(LTSA)
Translate
Model OK
Type Checking
Indirectly Verified
(avoidance of state explosion)
Java Code

24. Uncertainty Management with Git

25. Unit Testing Type Checking iArch-U Weaving & Test Execution
Archface-U
Java Code {
void bubbleSort(Data data);,
void quickSort(Data data); }
class ... {
void bubbleSort
void quickSort
... }
Type Checking
iArch-U
Weaving
&
Test Execution
bubbleSort
quickSort
Possibility
bubbleSort
Aspect
(AspectJ)
bubbleSort(foo);
bubbleSort(bar);
...
quickSort
Generate
Test Cases

26. Summary
and
Ongoing Work

27. Ongoing Work Extension to Probabilistic Programming
Archface-U dealing with probability
Type system for probabilistic programming
Probabilistic model checking
Extension to A/B Testing
uncertain component uStudentController extends StudentController{ {
@ExecWeight(4) void filterStudent(JTable table);,
@ExecWeight(1) void colorStudent(JTable table); }