Cataloging and
Detecting Architectural
Bad Smells
Joshua Garcia, Daniel Popescu, and
Nenad Medvidovic, University of
Southern California
Yuanfang Cai, Drexel University
Motivation – Refactoring Architecture
• Successful systems are maintained over multiple years
• System’s Life-Cycle Properties worsen over time
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•
•
•
Understandability
Testability
Extensibility
Reusability
• Restructuring/Refactoring helps to improve life-cycle properties
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Code Smells
• When and where to refactor a software system’s architecture?
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Motivation – iRODS - Prescriptive
Source: https://www.irods.org/index.php/Introduction_to_iRODS
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Motivation – iRODS - Descriptive
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Contribution and Goals
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Categorization of Architectural Smells
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•
•
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Separation of Concerns
Coupling and Cohesion
Novel Architectural Recovery Technique
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•
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Identification of Elements
Concern Meta-Classification
Novel Architecture Representation
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•
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Components, Connectors, Interfaces, Data Elements, Concerns
Extended Augmented Constraint Network
Design Structure Matrix
Architectural Smell Detection
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Connector Envy - Example
• Component exhibiting interaction-related functionality that
should be delegated to connector
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Reusability, understandability, testability
• StrategyAnalyzerAgent from Emergency Response System
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Architectural Recovery for Smells
• Component identification
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Hierarchical clustering
Concerns through topic modeling
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SAA – “strategy,” “rule,” “region”
• Connector identification
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Pattern matching, Supervised Learning
• Interface and Data Element Identification
• Concern Meta-classification
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Application-specific or application-independent concern
Supervised Learning
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Component Identification
1
f1, f2, … fn
2
f1, f2, … fn
n
f1, f2, … fn
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Component Identification
1
0, 1, … 1
2
0, 1, … 0
.
.
.
n
1, 0, … 1
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Component Identification
1
0, 1, … 1
Cluster
Cluster
2
0, 1, … 0
1, 0, … 0
3.
1,
. 1, … 0
.
n
1, 0, … 1
1, 1, … 1
4
…
n-1
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Component Identification
Cluster 1 1
Component
B
D
A
Cluster
2 2
Component
E
C
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Concerns through Topic Modeling
Component 1
Stream
UI
Component 2
Events
Weather
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Concerns through Topic Modeling
Word
Word
Probability
Probability
Send
Temperature 0.2
0.7
Receive
Wind
0.4
0.1
Event
Humid
0.4
0.2
Component 2
Events
Weather
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Connector Identification
Component 1
Stream
UI
Component 2
Events
Weather
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Connector Identification
Component 1
Stream – 0.1
UI – 0.9
Component 2
Events – 0.1
Weather - 0.9
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Connector Identification
Component 1
Cluster
3
Connector
Events – 1.0
Stream – 0.1
UI – 0.9
Component 2
Events – 0.1
Weather - 0.9
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Novel Architecture Representation
• Extended Augmented Constraint Network
• Uniform, formal way of capturing of architectural
decisions
• Constraint network, design rule, cluster set,
concerns from topic models
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Design Structure Matrix of ERS
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Future Work
• Evaluation of the recovery technique
• Evaluation of the smell detection
• Expansion of the catalog
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Thank You
• Thank You
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