This document presents a pilot study that evaluates the prevalence of architectural anti-patterns and code quality issues in student projects from an object-oriented programming course. It identifies common problems related to architectural patterns and code smells, suggesting that a project-based approach to teaching can lead to poor quality outcomes. The study aims to inform educators about prevalent issues to improve the teaching of software quality concepts.

1. Automatic Assessment of Architectural
Anti-patterns and Code
Smells in Student Software Projects
Marco De Luca, Sergio Di Meglio, Anna Rita Fasolino, Luigi
Libero Lucio Starace, Porfirio Tramontana,
University of Naples “Federico II”
2nd Workshop on evaLuation and assEssment in softwARe
eNgineers’ Education and tRaining
LEARNER 2024 @ EASE 2024
Salerno, Italy, June 21st, 2024.

2. Motivations
 A project-based approach for teaching object-oriented
programming has many advantages:
 Provides an early introduction to software design
concepts
 Encourages students to work in groups, share
information, understand the first concept of teamworking
 Integrates multidisciplinary knowledge, e.g. Software
Engineering, Programming and Database
 Allows students to observe and appreciate the concrete
result of their work
 In our experience as teachers, the project-oriented
approach also positively affects students' performance
compared to an analytical approach
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3. Problem
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Students focus on
the result to be
achieved in
functional terms
The quality of the
project is often
poor

4. Typical Quality Issues in Student’s projects
 Architectural Issues
 Architectural patterns maintain higher the
project quality
but are often neglected by students in favour of
easier programming solutions
 Code Issues
 Clean Code recommendations are often
neglected
many code smells can be found in student’s code
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5. Our contribution:
general idea
 We have started a long-
term experimentation
aiming at:
 Measuring the
occurrence of quality
issues in student’s
projects
 Improving the teaching
by early introducing
quality concepts
 Measuring the
improvement in quality
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6. Current
Contribution
In this paper we will present
a first pilot study aiming at
measuring the occurrence of
some common architectural
and code issues in the
projects realized by all the
students of a Bachelor
Degree programming course
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2024

7. Research questions
RQ1: How common
are architectural
pattern violations in
student projects?
RQ2: How common
are code quality
issues in student
projects?
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8. Context
 Object Oriented Programming
course
 2nd Year of Bachelor Degree in
Computer Science @ University
of Naples Federico II
 Students previously had a
first programming course at
1st year
 The course is taken in
parallel with a Database
course
 48 lecture hours (6 ECTS)
 Java language
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21st, 2024

9. Assessment
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21st, 2024
Students are divided in teams of 2 or 3
Different projects were assigned to each group
Students has to upload and present
their project after the end of the course
Only after project presentation, the students can
sustain an individual written exam, followed by
an oral exam
The completeness and correctness of
the project were mainly considered
Also the project quality influenced the teacher’s
judgement

10. Architectural
Issues
 During the course the
teacher presented a
specific architectural
pattern explaining its
benefits and drawbacks
 The students never
had previous
teaching about
design patterns
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2024

11. The proposed Architectural
Pattern
 Similar to a Boundary –
Controller – Entity, with the
introduction of a DAO pattern
 4 allowed interactions
GC
CD
CM
 8 unallowed interactions
GD
GM
DC
MC
DM
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12. Measuring Architectural Pattern Violations
 ArchUnit is an open source project able to define
architectural pattern violations in form of JUnit Test
Cases
 Two of the authors implemented ArchTest cases by
substituting the name of the packages used by students in a
set of predefined test cases
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13. Code Quality Assessment
 The most popular tool for measuring code
quality issues is SonarQube
 677 Java rules
 Issues are categorized:
 By type (Bug, Vulnerability and Code Smell)
 By severity (Critical, Major, Minor, Info)
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14. Case
study
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2024,
Salerno,
June
21st,
2024
Object Oriented
Programming
course taken in
2021/22
50 students
concluded 26
projects
Three different
projects were
proposed
Average
complexity of
the projects:
41 classes and
4647 NCLOCs

15. Results : RQ1
Number and percentage of projects presenting at
least one disallowed interaction
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16. Results : RQ1
Number and percentage of projects presenting at
least one disallowed interaction
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The direct access to model classes was a shortcut
for students but implies inestricable coupling for
the project

17. Results : RQ1
Number and percentage of projects presenting at
least one disallowed interaction
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GUI and Data Access Objects should remain
independent between them

18. Results : RQ2
More common code issues found by SonarQube
(number and percentage presenting at least one
occurrence of the issue)
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19. Results : RQ2
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 Open resources can cause performance problems

20. Results : RQ2
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 Duplicated string literals can cause incoherences during code
maintenance
 They should have been substituted by constant resources, also to ease
localization
 High Cognitive complexity makes maintenance more difficult

21. Results : RQ2
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 Log messages should be redirected to log files with an appropriate
formatting
 Unused assignments and imports and equal branches are symptoms
of code smells due to lack of code review

22. Results : RQ2
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 Naming conventions are useful to improve code understandability

23. Conclusions
LEARNER
2024,
Salerno,
June
21st,
2024
This first pilot experiment has
shown which types of
architectural patterns and code
issues are most common in
student projects
These preliminary results can
provide useful indications to
teachers who want to teach
concepts related to the quality of
projects regarding which are the
most common errors and the
topics to be treated with greater
insistence

24. Future Works
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21st, 2024
To extend the experimentation to different
courses and different editions of the same
course
To measure whether more teaching about
code and architecture quality can reduce the
occurrence of issues