CS746 Software Architecture Organizational Meeting

1
CS746 Software Architecture Organizational
Meeting

• Instructor Prof. Richard C. Holt
• TA Jingwei Wu

2
Overview

• Course Assignments and Project
• Introduction to JGrok Algebraic Calculator
• BFX-based Architecture Extraction Pipeline
• Volunteers to present papers next week

3
Course Assignments

• Case software system Mozilla
• Three course assignments
• Conceptual architecture (Documented)
• Concrete architecture (Implemented)
• Architecture refactoring
• Historical (Evolutionary evidence)
• Future (Forward engineering)
• Each assignment takes two weeks
• Team work (23 persons per team)

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Conceptual Architecture

• Read a wide variety of software documents
• Release notes
• Developer docs
• Technical article
• Research papers
• Source code comments
• Previous course reports on Mozilla
• Warning The architecture of Mozilla has been
  fundamentally altered. You cannot simply reuse
  previous course material.
• The goal is to understand the software domain

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Conceptual Architecture Cont.

• Submit a technical report on the conceptual
  architecture of Mozilla.
• Describe major components
• Describe component interactions
• Clarify architectural style and principles
• Concentrate on goals and requirements
• Concurrency, evolvability, performance, etc.
• Submission date Tuesday, Sept. 28, 2004.

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Conceptual Architecture of Linux
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Concrete Architecture

• Extraction
• Mozilla implemented in C/C
• We use BFX, a binary file extractor
• Abstraction
• Construct containment hierarchy
• Larger subsystems contain smaller subsystems
• View/Edit
• We use LSEdit, a landscape view editor

8
Concrete Architecture Cont.

• Submit a technical report on the concrete
  architecture of Mozilla.
• Organization similar to Assignment I
• Describe the architecture at the highest level of
  abstraction
• Describe at least one of the top-level subsystems
• Explain why the conceptual and the concrete
  disagree
• Submission date Tuesday, Oct. 19, 2004

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Concrete Architecture of Linux
10
Concrete Architecture ofFile Subsystem in Linux
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Architecture Refactoring

• Two options for this assignment
• Historical architecture refactorings
• Document architectural changes in the past
• Understand how the architecture evolved over time
• Extract several versions (at least THREE)
• Future architecture refactorings
• Describe a desirable feature
• Identify an architectural problem
• Refactor the current architecture
• Focus on the most recent version
• Report Submission date Tuesday, Nov. 09, 2004

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Course Project

• Five Options
• Architecture Refactoring Future
• Architecture Refactoring Historical
• Architectural Repair
• New Tools
• New Landscapes
• Project due Tuesday, Dec 07 2004

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Introduction to JGrok

• A simple scripting language
• A relational algebraic calculator
• Powerful in manipulating binary relations
• Widely used in architecture transformation
• Online documentation

http//swag.uwaterloo.ca/j25wu/projects/grokdoc/i
ndex.html
http//swag.uwaterloo.ca/nsynytskyy/grokdoc/index
.html
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JGrok Features

• Set operations
• Union (), intersection (), subtraction (-),
  cross-product (X)
• Binary relation operations
• Union (), intersection (), subtraction (-),
  composition (o, ), cat-composition (),
  projection (.), domain (dom), range (rng),
  identity (id), inverse (inv), entity (ent),
  transitive closure (), and reflective transitive
  closure ()
• Graph pattern matching (like Prolog)
• dataid,name,salary _at_nameid,name
  salaryid,salary
• Relation selection, projection
• data1 Peter. 2 gt 50000
• names data1, 2

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JGrok Features Cont.

• Programming constructs
• if else
• for, while
• Arithmetic, comparison, logical operators
• , -, , /,
• lt, lt, , gt, gt, !
• !, ,
• Regular expression matching
• , !
• functions0 nsFrame.

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JGrok Scripts (1)

• jGrok
• gtgt cat Garfield, Fluffy
• gtgt mouse Mickey, Nancy
• gtgt cheese Roquefort, Swiss
• gtgt animals cat mouse
• gtgt food mouse cheese
• gtgt animalsWhichAreFood animals food
• gtgt animalsWhichAreNotFood animals food
• gtgt animalsWhichAreFood
• Mickey
• Nancy
• gtgt animals food
• Garfield
• Fluffy
• gtgt food
• 4
• gtgt mouse lt food
• True
• gtgt

gtgt chase cat X mouse gtgt chase Garfield
Mickey Garfield Nancy Fluffy Mickey Fluffy
Nancy gtgt gtgt eat chase mouse X cheese gtgt
eat Garfield Mickey Garfield Nancy Fluffy
Mickey Fluffy Nancy Mickey Roquefort Mickey
Swiss Nancy Roquefort Nancy Swiss
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JGrok Scripts (2)

• gtgt Mickey . eat
• Roquefort
• Swiss
• gtgt eat . Mickey
• Garfield
• Fluffy
• gtgt
• gtgt eater dom eat
• gtgt food rng eat
• gtgt chasedBy inv chase
• gtgt topOfFoodChain dom eat rng eat
• gtgt bottomOfFoodChain rng eat dom eat
• gtgt bothEatAndChase   eat chase
• gtgt eatButNotChase eat chase
• gtgt chaseButNotEat chase eat
• gtgt secondOrderEat   eat  o  eat
• gtgt anyOrderEat eat

Programming constructs if expression
statements else statements while
expression statements for variable in
expression statements
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Extraction Pipelines
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BFX-Based Pipeline
Source code
Step 1
Build
Hierarchical Decomposition
Object code
Step 2
BFX
Program facts
Step 3
Link
Step 4
Add contain
Step 5
System Models
LSEdit
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BFX-Based Pipeline Step 1

• Build the system
• Download Mozilla (http//www.mozilla.org/)
• Download Mozilla 1.7.2
• Download the latest development version via CVS
• Build Mozilla
• Use default build scripts (make utilities)
• cd mozilla
• gmake f client.mk build

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BFX-Based Pipeline Step 2

• Extract facts using BFX
• cd ..
• bfx find mozilla -name .o -o
  mozilla.bfx.ta
• Extract facts from each object module and write
• all facts to an output file called
  mozilla.bfx.ta.

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BFX-Based Pipeline Step 3

• Link extracted facts (resolve references to
  external definitions)
• jGrok QLDX/script/bfx/rawlink.ql
  mozilla.bfx.ta mozilla.raw.ta
• Extract facts from each object module and write
• all facts to an output file called
  mozilla.raw.ta.

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BFX-Based Pipeline Step 4

• Create a hierarchical subsystem decomposition
• Create a contain file called mozilla.contain in
  RSF
• contain mozilla editor.ss
• contain mozilla layout.ss
• contain layout.ss html.ss
• contain html.ss mozilla/layout/html/document/src/n
  sFrameSetFrame.o
• Impose contain on raw data (file-level graph)
• jGrok QLDX/script/bfx/addcontain.ql
  mozilla.contain mozilla.raw.ta mozilla.con.ta

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BFX-Based Pipeline Step 5

• Create landscape views
• Add schema
• schema mozilla.con.ta mozilla.ls.ta
• Edit views
• lsedit mozilla.ls.ta

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Volunteer Presenters

• Bowman Linux as Case Study Extracted
  Architecture
• Presenter Omar Zia
• Garlan and Shaw Introduction to Software
  Architecture
• Presenter Alan Grosskurth