Extracting missing important links and models from software is the key to success of its maintenance such as specifying locations that need correction. This talk firstly introduces two novel techniques for recovering traceability links precisely between requirements and program source code: log-based interactive recovery (CAiSE'15) and transitive recovery (ICSME'15 ERA). Secondly the talk introduces two novel preventive maintenance techniques employing behavioral model extraction and model checking targeting Ajax applications: design pattern based invariants verification (ASE'13) and delay-based mutation (ASE'14). Hironori Washizaki is head and associate professor at Global Software Engineering Laboratory, Waseda University, Japan. He is also visiting associate professor at National Institute of Informatics, and, visiting professor at Ecole Polytechnique de Montreal during his sabbatical stay till Dec 2015. He received PhD in Information and Computer Science from Waseda University in 2003. His research interests include software and systems requirements, architecture, reuse, maintenance, quality assurance, and education. He has served on the organizing committees of many international conferences (such as ASE, ICST, SPLC, CSEE&T, SEKE, BICT and APSEC) as well as editorial boards of several international journals (such as Int. J. Soft. Eng. Know. Eng. and IEICE Trans). He also has served at various professional societies such as IEEE Computer Society Japan Chapter Chair, SEMAT Japan Chapter Chair, IPSJ SamurAI Coding Director, and ISO/IEC/JTC1/SC7/WG20 Convenor. http://www.washi.cs.waseda.ac.jp/?page_id=2

1. Software Maintenance Support by
Extracting Links and Models
Hiro - Hironori Washizaki
Waseda University
Twitter: @Hiro_Washi washizaki@waseda.jp
http://www.washi.cs.waseda.ac.jp/
Thanks to: Ryosuke, Kazuki, Yuta and other collaborators!
Latece Seminar, Nov 11, 2015 @ UQAM, Montreal

2. • Assoc. Prof., Head, Global
Software Engineering
Laboratory, Waseda University
• Visiting Assoc. Prof., National
Institute of Informatics
• Visiting Prof., Ecole
Polytechnique de Montreal
• Convenor, ISO/IEC SC7/WG20
• Chair, IEEE CS Japan Chapter
• Chair, SEMAT Japan Chapter 2
Hironori Washizaki

3. Waseda University
Global Software Engineering Lab.
• SE research in global
development era
– Analysis and reuse
– Quality assurance
– Agile and patterns
– SE education
• 5 professors
• 15+ partners
• 25 students (5 from
China, Indonesia,
Afganistan) 3

4. Software maintenance matters!
60–90% of total costs
4
B. Lientz and E. Swanson, Software Maintenance Management. Reading, Ma.: Addison-Wesley, 1980.
J. Conejero, E. Figueiredo, A. Garcia, J. Hernández and E. Jurado, "On the Relationship of Concern
Metrics and Requirements Maintainability,” Information and Software Technology, vol.54, no.2, 2012.

5. How can we support?
5
Requirements
Design
Program
source
code

6. How can we support?
6
Requirements
Design
Program
source
code
Tracing
artifacts
Tracing
artifacts
Log-based interactive recovery [CAiSE’15]
Transitive recovery [ICSME’15 ERA]
Ryosuke Tsuchiya, Hironori Washizaki, Yoshiaki Fukazawa, Keishi Oshima, and Ryota Mibe,“Interactive Recovery of Requirements
Traceability Links Using User Feedback and Configuration Management Logs,” 27th International Conference on Advanced
Information Systems Engineering (CAiSE 2015)
Kazuki Nishikawa, Hironori Washizaki, Yoshiaki Fukazawa, Keishi Ohshima, Ryota Mibe, “Recovering Transitive Traceability Links
among Software Artifacts,” 31st IEEE International Conference on Software Maintenance and Evolution (ICSME 2015), ERA Track

7. Traceability links?
• Relationships among software artifacts
• Key to ensure consistency among artifacts [Antoniol‘00]
7G. Antoniol, B. Caprile, A. Potrich and P. Tonella, "Design-Code Traceability for Object-Oriented Systems," Annals of
Software Engineering, vol. 9, no. 1-4, pp. 35-58, 2000
Requirement
Source code
Run
automated
test
Run basic
test
Add
tests
Automate.c X
Basic.c X
TestDB.c X
TestRun.c X X

8. Facts of traceability links
• Rarely established explicitly [Lucia’12]
• Most of existing recovery techniques employing
Information Retrieval (IR) approaches such as TF/IDF
and Vector Space Model (VSM)
8
A. De Lucia, et al., "Information Retrieval Methods for Automated Traceability Recovery," in Software and Systems
Traceability, 1st ed., J. Cleland-Huang, O. Gotel and A. Zisman, Ed. New York: Springer, p. 71-98, 2012.
Automated test
Automated.c
MyMem.c
Initialization
Requirement
基本テスト
Basic.c
NGOK

9. Interactive recovery utilizing call relationships
Rank Requirement Code file Score Recommended Correct
1 Recover link
2 Recover link
3 Recover link
・・・ ・・・
9
Recover link
・・・
LinkPresenter.java
・・・
LinkRecover.java
ScoreCalc.java
・・・
Call
Ryosuke Tsuchiya, Hironori Washizaki, Yoshiaki Fukazawa, Keishi Oshima, and Ryota Mibe,“Interactive Recovery of Requirements
Traceability Links Using User Feedback and Configuration Management Logs,” 27th International Conference on Advanced
Information Systems Engineering (CAiSE 2015)

10. Interactive recovery utilizing call relationships
Rank Requirement Code file Score Recommended Correct
1 Recover link LinkRecover.java 0.98 not yet
2 Recover link LinkPresenter.java 0.65 not yet
3 Recover link ScoreCalc.java 0.30 not yet
・・・ ・・・ ・・・ ・・・
10
Recover link
・・・
LinkPresenter.java
・・・
LinkRecover.java
ScoreCalc.java
・・・
☑
Call
☑
Ryosuke Tsuchiya, Hironori Washizaki, Yoshiaki Fukazawa, Keishi Oshima, and Ryota Mibe,“Interactive Recovery of Requirements
Traceability Links Using User Feedback and Configuration Management Logs,” 27th International Conference on Advanced
Information Systems Engineering (CAiSE 2015)

11. Interactive recovery utilizing call relationships
Rank Requirement Code file Score Recommended Correct
1 Recover link LinkRecover.java 0.98 not yet
2 Recover link ScoreCalc.java 0.30 Recommended
3 Recover link LinkPresenter.java 0.65 not yet
・・・ ・・・ ・・・ ・・・
11
Recover link
・・・
LinkPresenter.java
・・・
LinkRecover.java
ScoreCalc.java
・・・
☑
Call
☑
Ryosuke Tsuchiya, Hironori Washizaki, Yoshiaki Fukazawa, Keishi Oshima, and Ryota Mibe,“Interactive Recovery of Requirements
Traceability Links Using User Feedback and Configuration Management Logs,” 27th International Conference on Advanced
Information Systems Engineering (CAiSE 2015)

12. Automated test
Log-based recovery
12
Automated test
automate・・
・・XML・・・
・test・・・・・・
Requirement
automate
XML
test
automate
XML
Keywords
High
TF-IDF value
Proper noun
Filtered
by experts
automate
XML
Revision: 137
Author: anilsaharan
Date: 2011/8/20 9:35:13
Message:
Changes for fixing XML tag issue
----
Modified : /trunk/CUnit/Sources/Tool/Process.c
Process.c
・・・
Ryosuke Tsuchiya, Hironori Washizaki, Yoshiaki Fukazawa, Keishi Oshima, and Ryota Mibe,“Interactive Recovery of Requirements
Traceability Links Using User Feedback and Configuration Management Logs,” 27th International Conference on Advanced
Information Systems Engineering (CAiSE 2015)

13. Experiment: Japanese enterprise system
• 80,000 LOC, 192 requirements, 694 Java code files,
7090 revisions in Subversion
• 726 known links as correct answer
13
Ryosuke Tsuchiya, Hironori Washizaki, Yoshiaki Fukazawa, Keishi Oshima, and Ryota Mibe,“Interactive Recovery of Requirements
Traceability Links Using User Feedback and Configuration Management Logs,” 27th International Conference on Advanced
Information Systems Engineering (CAiSE 2015)

14. Transitive recovery
14
Code Design Test Score
C1 Da Tx 0.16
C1 Da Ty 0.14
C1 Db Tx 0.03
• Vector Space Model (VSM) for basic recovery
Source code Design Test case
Code Design Similarity
C1 Da 0.4
C2 Db 0.3
Design Test Similarity
Da Tx 0.40
Da Ty 0.35
Db Tx 0.10
Kazuki Nishikawa, Hironori Washizaki, Yoshiaki Fukazawa, Keishi Ohshima, Ryota Mibe, “Recovering Transitive Traceability Links
among Software Artifacts,” 31st IEEE International Conference on Software Maintenance and Evolution (ICSME 2015), ERA Track

15. Experiment: EasyClinic
• Target link: 47 Java code ⇔ 63 test docs
• Supportive artifacts: 20 design docs or 30 use cases
• Effectiveness varies with supportive artifacts
15Kazuki Nishikawa, Hironori Washizaki, Yoshiaki Fukazawa, Keishi Ohshima, Ryota Mibe, “Recovering Transitive Traceability Links
among Software Artifacts,” 31st IEEE International Conference on Software Maintenance and Evolution (ICSME 2015), ERA Track

16. How can we support?
16
Requirements
Design
Program
source
code
Yuta Maezawa, Kazuki Nishiura, Hironori Washizaki, Shinichi Honiden, “Validating Ajax Applications Using a Delay-Based Mutation
Technique,” 29th IEEE/ACM International Conference on Automated Software Engineering (ASE 2014)
Yuta Maezawa, Hironori Washizaki, Yoshinori Tanabe and Shinichi Honiden, “Automated Verification of Pattern-based Interaction
Invariants in Ajax Applications,” 28th IEEE/ACM International Conference on Automated Software Engineering (ASE2013)

17. How can we support?
17
Requirements
Design
Program
source
code
Reversing
model
Detecting
problems
Detecting
problems
Ajax model extraction and verification
[ASE’13][ASE’14]
Yuta Maezawa, Kazuki Nishiura, Hironori Washizaki, Shinichi Honiden, “Validating Ajax Applications Using a Delay-Based Mutation
Technique,” 29th IEEE/ACM International Conference on Automated Software Engineering (ASE 2014)
Yuta Maezawa, Hironori Washizaki, Yoshinori Tanabe and Shinichi Honiden, “Automated Verification of Pattern-based Interaction
Invariants in Ajax Applications,” 28th IEEE/ACM International Conference on Automated Software Engineering (ASE2013)

18. 18
window.onload = setEventHandler;
function setEventHandler() {
$(“reg_type”).onchange = calcPrice;
・・・
$(“reg_addcart”).onclick = addCart;
};
function calcPrice() { ・・・ };
function addCart() {
if(isValidInput()) {
reqRunTrans();
} else {
alert(“Invalid user inputs”);
}
};
function reqRunTrans() {
new Ajax.Request(“runTrans.php”, {
method: “GET”, parameters: getParams(),
onSuccess: succeeded });
};
function succeeded() { disableAll();
jumpToConfirm();
};Yuta Maezawa, Hironori Washizaki, Yoshinori Tanabe and Shinichi Honiden, “Automated Verification of Pattern-based Interaction
Invariants in Ajax Applications,” 28th IEEE/ACM International Conference on Automated Software Engineering (ASE2013)

19. 19
Extracted finite state machine
Yuta Maezawa, Hironori Washizaki, Yoshinori Tanabe and Shinichi Honiden, “Automated Verification of Pattern-based Interaction
Invariants in Ajax Applications,” 28th IEEE/ACM International Conference on Automated Software Engineering (ASE2013)

20. • #70 programming and usability patterns
• Potential faults: might not be revealed by testing
Ajax (Asynchronous JavaScript + XML)
Design Patterns [Mahamoff’06]
20
[Mahamoff’06] M. Mahamoff, “Ajax Design Patterns”, O’Reilly Media Inc., 2006.
E.g. User Action
“Prevent multiple
calls of specific user
event handler”
Yuta Maezawa, Hironori Washizaki, Yoshinori Tanabe and Shinichi Honiden, “Automated Verification of Pattern-based Interaction
Invariants in Ajax Applications,” 28th IEEE/ACM International Conference on Automated Software Engineering (ASE2013)

21. Duplicate
order
21
Verifying invariants of specified pattern
Yuta Maezawa, Hironori Washizaki, Yoshinori Tanabe and Shinichi Honiden, “Automated Verification of Pattern-based Interaction
Invariants in Ajax Applications,” 28th IEEE/ACM International Conference on Automated Software Engineering (ASE2013)

22. 22
window.onload = setEventHandler;
function setEventHandler() {
$(“reg_type”).onchange = calcPrice;
・・・
$(“reg_addcart”).onclick = addCart;
};
function calcPrice() { ・・・ };
function addCart() {
if(isValidInput()) {
$(“addCart”).disabled = true;
reqRunTrans();
} else {
alert(“Invalid user inputs”);
$(“addCart”).disabled = false;
}
};
function reqRunTrans() {
new Ajax.Request(“runTrans.php”, {
method: “GET”, parameters: getParams(),
onSuccess: succeeded }); };
function succeeded() { disableAll();
jumpToConfirm(); };Yuta Maezawa, Hironori Washizaki, Yoshinori Tanabe and Shinichi Honiden, “Automated Verification of Pattern-based Interaction
Invariants in Ajax Applications,” 28th IEEE/ACM International Conference on Automated Software Engineering (ASE2013)

23. • Developers are concerned with interactions[Duhl’03]
• Interaction = event + callback
• Rules are necessary for distinguishing interaction-
related code fragments
Interaction-based state machine extraction
23
………………………………
………………………………
………………………………
………………………………
…………………………….…
………………………………
……………………………
function addCart() {…
………………………………
……………………..……
………………………………………
………………………………………
$(“addcart”).disabled=true;
………………………………………
………………………………………
……………………………………
…………
…………
…………
………………………………
………………………..……
………………………………
………………………………
………………………………
………………………………
………………………………
………………………………
………………………………
………………………………
…………………………
……………………………………………
……………………………………………
function setEventHandler() {
$(“addcart”).onclick=addCart;
……………………………………………
……………………………………………
……………………………………………
……………………………………………
……………………………………………
onclick
setEventHandler
ev
addCart
…disabled…
[c]
[!c]
[Duhl’03] J.Duhl, “White Paper: Rich Internet Applications”, IDC Technical Report’ 03.
Yuta Maezawa, Hironori Washizaki, Yoshinori Tanabe and Shinichi Honiden, “Automated Verification of Pattern-based Interaction
Invariants in Ajax Applications,” 28th IEEE/ACM International Conference on Automated Software Engineering (ASE2013)

24. Verification on Promela with LTL
24
Self interaction
User Server
active proctype
App () {…}
App model
active proctype
Interaction () {…}
Interaction model Faulty execution paths
Verification formulas (LTL)
Pattern Negative property
User Action <>(App_state == PreventFunc
&& App_event == UserEvent )
Yuta Maezawa, Hironori Washizaki, Yoshinori Tanabe and Shinichi Honiden, “Automated Verification of Pattern-based Interaction
Invariants in Ajax Applications,” 28th IEEE/ACM International Conference on Automated Software Engineering (ASE2013)

25. • Problem: Potential faults might not cause actual errors
• Assumption: Unexpected network latency make
potential faults executable.
• Solution: Delay-based mutation and testing
Delay-based mutation
25
<button onclick=“handleClick()” />
・・・
<script src=“handleClick.js” />
new DelayedRequest(3000).applyFunction(
$.get ,
“myscript.php”,
{ name: “ABC” }, function(data) {
alert(“Response is ” + data); }
);
Synchronous delay Asynchronous delay
Original code
S1
S2
S3
Late
response
reveals!
Assumes
immediate
response
Yuta Maezawa, Kazuki Nishiura, Hironori Washizaki, Shinichi Honiden, “Validating Ajax Applications Using a Delay-Based Mutation
Technique,” 29th IEEE/ACM International Conference on Automated Software Engineering (ASE 2014)

26. Case Study: industrial services
26
Subject
JS
[LOC]
#States #Trans.
#Invariants
verified
#Potential
faults
#Delay-
Dependent
faults
2020
Marketing
2,468 15 547 4 1 1
ECD China 880 32 508 3 2 1
Easy
Serviced
Apartments
3,523 34 602 3 1 1
Undefined
function call
Login failed
with correct
username and
password
Yuta Maezawa, Kazuki Nishiura, Hironori Washizaki, Shinichi Honiden, “Validating Ajax Applications Using a Delay-Based Mutation
Technique,” 29th IEEE/ACM International Conference on Automated Software Engineering (ASE 2014)

27. Summary
27
Reversing
model
Tracing
artifacts
Detecting
problems
Detecting
problems
Tracing
artifacts
Log-based interactive recovery [CAiSE’15]
Transitive recovery [ICSME’15 ERA]
Ajax model extraction and verification [ASE’13]
Ajax delay-based mutation [ASE’14]

28. 28
Feb 24-26 (due Dec 4)
asianplop.org
Mar 15 (due Dec)(TBD)
ppap.soccerlab.polymtl.ca
Mar 11 (due Jan 8)
samuraicoding.info
Mar 13-18 (due Sep 2016)
aster.or.jp/conference/icst2017/
10th IEEE International Conference on
Software Testing, Verification and Validation
IPSJ International AI Programming Contest