My slides from the Clean Code Days 2013 presentation.

1. Towards Clean Legacy Code
Lars Martin, Clean Code Days 2013, 11.09.2013

2. Towards Clean Legacy Code
§ Developer, Architect,
Consultant
§ Java Enterprise, Eclipse,
Continuous …
Who am I?

3. Agenda
+ introduction into model based
software modernization
approaches (software evolution)
+ introduction of Eclipse based
tooling
− full migration of legacy systems
“Make sure you know what the code does
before you attempt any modifications, don't just
jump in.”
Towards Clean Legacy Code

4. Towards Clean Legacy Code
Motivation
§ legacy system
§ heavy database access
§ ORM è java.sql.*
§ new team
©
Katharina
Bregulla
/
pixelio.de

5. Towards Clean Legacy Code
Motivation
§ Raising Questions
Ø which tables will be accessed?
Ø will other tables (modules) be
accessed?
Ø if yes, migrated already?
Ø automation possible?
©
Katharina
Bregulla
/
pixelio.de

6. Towards Clean Legacy Code
Horseshoe-Model
PIM
PSMPSM’
PIM’
Code’ Code
ForewardEngineering(MDA)
ReverseEngineering(ADM)
Re-Engineering
Architecture
Transformation
Reverse engineering: ”… is the process
of analyzing a software system to
create representations of the system
at a higher level of abstraction.”
Re-Engineering: “... is the analysis and
modification of a software system to
change its form and implement it in its
new form.”
(Forward) Engineering: “… is the way
of designing systems, starting from
abstract logical and implementation
independent specification to gradually
lead to the implementation of a
physical system. ©
unknown

7. Towards Clean Legacy Code
MoDisco - Concepts
MoDisco
Eclipse Modeling
Source Code
Databases
Metrics
Norm checking
Configuration
Files
Restruct. Code
Migrated Code
Documentation
Impact Analysis
Models
Viewpoints
..other

8. Towards Clean Legacy Code
MoDisco - Modernization Phases
Models
Discover
Viewpoints
UnderstandExisting Artifacts
Software Artifacts
• Source Code
• Configuration
• Tests
• Database
• …
New
Artifacts
Transform

9. Towards Clean Legacy Code
MoDisco – Use Cases
©
Michael
Bührke
/
pixelio.de

10. § Quality Assurance (Metrics, ...)
§ Documentation (Structure, Dataflow, …)
§ Refactorierung (Design Pattern, Standards, …)
§ Migration (Framework, Architecture, …)
Towards Clean Legacy Code
MoDisco – Use Cases
©
Michael
Bührke
/
pixelio.de

11. Practical
Session (1/2)
Towards Clean Legacy Code

12. JUnit4
é
JUnit3
©
Katharina
Wieland
Mülle
/
pixelio.de
Towards Clean Legacy Code
Practical Session

13. JUnit3
Queries
JUnit3
Facet
JUnit3
Customization
java.ecore
uses uses
customizes extends
conforms to
Java EMF Model
Towards Clean Legacy Code

14. Practical
Session (2/2)
Towards Clean Legacy Code

15. Abstract Factory,
Adapter, Bridge,
Builder, …, Singleton,
…, Visitor
©
kiramain
/
pixelio.de
Towards Clean Legacy Code
Practical Session

16. Towards Clean Legacy Code
Conclusion
ü Customizability
o Metamodels
o M2M, M2T
ü Extensive
o Discoverer
o Queries
ü Workflow
ü DSL (Xtext, …)
ü (Focus on Java)
ü Entry barriers
ü Toolset
©
Gerd
Altmann
/
pixelio.de

17. ©
Mario
De
Ma?a
/
pixelio.de
ü Metrics on software maintainability
o bugs / commits per time unit
o committer per time unit
o …
ü Identification of variants within branches
o modularization
o …
ü Sync domain model <−> DB
Towards Clean Legacy Code
Outlook

18. ©
Gerd
Altmann
/
pixelio.de

19. Master Thesis / Abschlussarbeit –
Software Engineering
Aufgabengebiet:
• Entwicklung von Methoden zur
Informationsgewinnung
• Implementierung der Methoden mittels Eclipse
basierter Technologien
Studienbereiche:
• Informatik und -Informatik
©
Willi
Heidelbach
/
pixelio.de

20. SMB GmbH – Plauenscher Ring 21 – D-01187 Dresden
Dipl.-Inf. Lars Martin
+49-(0)173-64 24 461
lars.martin@smb-tec.com