FermaT DOC Redocumentation of legacy systems

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FermaT DOCRedocumentation of legacy systems

• STRL Seminar
• Stefan Natelberg
• 25. May 2006

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Outline

• Overview
• Properties of a legacy system
• Reverse engineering
• Redocumentation
• Related Work
• The Rigi Environment
• The FermaT System
• FermaT - DOC
• Design overview
• Program tree
• Example of use

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Overview
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Properties of a legacy system

• Very large scale
• Written in a low level language
• Part of a legacy environment
• No documentation
• Business critical

A legacy system can contain millions of lines of
code
The example code for this project is written in
IBM/360 assembler
The example code is part of an IBM/360
environment
A legacy system has no or inconsistent
documentation
A legacy system allows usually no long downtime
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Reverse Engineering
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Redocumentation
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Redocumentation

• Part of reverse engineering
• Restoring of documentation
• Shows different views of a legacy system
• Call Graph
• Flow Chart
• AST
• UML diagram
• Text (e.g. JavaDoc)
• Provides an abstraction of a system

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Related Work
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The Rigi Environment

• Developed since 1995 at the University of
  Victoria
• Extract information from the source code
• Provides different views of a system
• Consists of three framework components
• Rigi Reverse
• Rigi Server
• Rigi Edit

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The Rigi Environment
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The Rigi Environment
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The FermaT System
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FermaT - DOC
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Design Overview
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Program Tree
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Example of use
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Many thanks for your questions!