CSIS3600 Systems Analysis and Design

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CSIS3600 Systems Analysis and Design

• Class 6 - CASE Tools

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CASE Tools

• The term Computer Aided Software Engineering
  (CASE) was born as a result of the need to
  provide structure to systems development efforts.
  (Many IS professionals thought that the software
  development process needed an engineering
  flavor that would help to establish the use of
  common techniques, standard methodologies and
  automated tools).

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CASE Tools

• The earliest commercial CASE tools date back to
  1982. These tools were heavily focused on
  supporting diagramming. By 1985, CASE became big
  in software engineering circles. By 1990, it was
  reported that there were over 470 CASE tool
  vendors with an estimated market of 4.8 billion
  with growth expected to exceed 13 billion by the
  end of the decade.

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Need for CASE

• Computer technology is expanding rapidly.
• Software applications are proliferating.
• New applications are emerging and there exists a
  need to maintain what is already in place. (More
  efficient ways to develop software applications
  are required.)
• Software development methodologies began to
  appear and formalized training and education was
  initiated for following a methodology for
  software development.

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Some Trivia

• Software Trivia It is estimated that there are,
  today, almost 500 programming languages in active
  use representing billions and billions of lines
  of code. Conservative estimates put the number of
  lines of COBOL in use at over 200 billion.
  Languages such as C, Basic, Pascal, Ada, Fortran,
  PL/1 and Jovial add another 200 billion lines to
  the COBOL total. A host of other languages
  including Algol, APL, CHILL, CMS2, CORAL, Forth,
  Lisp, Modula, Mumps, Prolog, Ratfor, and RPG, to
  name a few, account for the remainder. Even niche
  programming languages such as Natural account for
  over 10 billion lines of code in support of
  enterprise computing. This estimate doesn't even
  account for new programming environments such as
  Java.

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Sample Lines of Code
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What about Linux?
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Why CASE

• The purpose of CASE is
• to make it simpler to enact a single design
  philosophy with the goal to speed up the
  development process.
• to automate mundane tasks.
• to promote a central location for referencing
  system development activities and documents.

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What is CASE

• CASE is a collection of tools used to support the
  software development process.
• CASE tools support a wide variety of activities
  as identified in the SDLC.
• Cross life cycle tools support those activities
  that occur across multiple phases of the SDLC.
  Examples are project management, time estimates
  and creating documentation.

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Components of CASE

• A CASE environment contains a collection of
  tools. Not all environments provide all tools.
• CASE tools are divided into
• Upper CASE
• Lower CASE
• Cross Life Cycle CASE

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Components of CASE

• Upper CASE is focused in supporting project
  identification and selection, project initiation,
  project planning, analysis and design.
• Lower CASE provides support for the
  implementation and maintenance phases.
• Cross Life Cycle CASE supports activities that
  occur across multiple phases of the SDLC.

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Diagramming Tools

• Diagramming Tools provide the means for
  representing the system visually. They are used
  to show data flow, process flows,
  entity-relationships, etc.
• The diagramming tool provides a graphical tool
  set that can be used to draw the diagrams and
  most CASE tools even generate the database schema
  (separate tables defined in the database to store
  data) directly from the relationship diagrams.
• Diagramming capabilities are considered the most
  fundamental and indispensable component of a CASE
  environment.

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Sample Diagramming Tool - DataFlow
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Sample Diagramming Tool Entity Relationship
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Form and Report Generator Tools

• Form and Report Generator Tools provide automated
  tools for designing forms and developing report
  formats.
• These help to provide end users with prototypes
  of how the system will look and feel.

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Sample Form and Report Generator Tool
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Analysis Tools

• Analysis Tools generate reports that help to
  identify possible inconsistencies, redundancies
  and omissions in diagrams, forms and reports
  previously created.
• They help to insure that the data needed is
  entered into the system, flows through the system
  and can be reported out when needed.
• These tools also check for such things as
  redundancy, missing elements, incorrect flow of
  data, etc.

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Repository

• The Repository provides a centralized database
  that contains all diagrams, reports, forms, data
  structures and other definitions of the system.
• It serves as the nucleus of the system
  development environment and is paramount to the
  integration of the tools used at various stages
  of the SDLC.
• The repository can serve as the library of all
  information related to the system development
  project thereby providing means for facilitating
  project management and project sharing.

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Repository

• Further, repositories provide a vehicle for
  reusability because known development work is
  located in a common place facilitating reuse of
  resources for similar project.

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Sample Repository Reports Screen
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Documentation Generator Tools

• Documentation Generator Tools provide support for
  the generation of standard reports that can be
  maintained and shared throughout the development
  process.
• Enough said about documentation we all know how
  important it is but how it often slips through
  without being completed.

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Code Generators

• Code Generators automated systems that produce
  high-level program source code from diagrams and
  forms.
• (CASE generated source code often has to be
  edited by programmers.)

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CASE Usage Within the SDLC
SDLC Phase Key Activities CASE Tool Usage
Project identification and selection Display and structure high-level organizational information Diagramming and matrix tools to create and structure information
Project initiation and planning Develop project scope and feasibility Repository and documentation generators to develop project plans
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CASE Usage Within the SDLC
SDLC Phase Key Activities CASE Tool Usage
Analysis Determine and structure system requirements Diagramming to create process, logic and data models
Design Create new system designs Form and report generators to prototype designs analysis and documentation generators to define specifications
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CASE Usage Within the SDLC
SDLC Phase Key Activities CASE Tool Usage
Implementation Translate designs into an information system Code generators and analyzers, form and report generators documentation generators to develop system and user documentation
Maintenance Evolve information systems All tools are used (repeat life cycle)
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CASE and the SDLC
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Greatest Benefits of CASE

• The big benefits to using CASE come in the late
  stages of the SDLC system construction,
  testing, maintenance.
• CASE often lengths the time to completion of the
  early stages of the SDLC by 40 according to some
  estimates.
• This is because the design must be fully
  completed before using such automated tools as
  code generators, etc.

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Neat Features of CASE

• Reverse Engineering automated tools that read
  program source code as input and create graphical
  and textual representations of program
  design-level information.
• Reengineering Automated tools that read program
  source code as input, perform an analysis of the
  programs data and logic, and then automatically
  or interactively alter an existing system.

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Constraining Factors of CASE

• Start-up costs can be high prices range from
  5000 per analyst to 50,000
• Year cost estimate - 5,000-15,000 per year per
  analyst
• Learning curve is high Many CASE applications
  are complex, with many sophisticated tools
• CASE software dictates a way of doing things
• CASE tools cannot easily share information
  between tools

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What is the use of CASE?

• Many organizations use varying tools or aspects
  of CASE.
• Most widely used features are the diagramming
  tools
• Next commonly used is the repository
• Provides integration of documentation
• Promotes consistency when changes are made

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Emerging Tools for Object Oriented Design

• Object Oriented Design is an extremely important
  area of development and CASE tools for Object
  Oriented Design are emerging and maturing.

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Tools for OOAD

• You are probably familiar with visual development
  tools. These tools are extremely powerful. They
  allow users to create new user interfaces,
  reports and other features in a fraction of the
  time previously required. Common visual
  development tools include PowerBuilder by
  Powersoft, Delphi by Borland International, Visio
  (now owned by Microsoft) and Visual Basic by
  Microsoft.

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CASE Tool Resources

• On-line resources for CASE tools
• Directory of CASE TOOLS http//www.qucis.queensu.
  ca/Software-Engineering/tools.html
• CASE Tools Listing and other CASE References
  http//www.itmweb.com/case.htm
• These sites will allow you to download an
  evaluation (beware Rational is 51MB!! you might
  prefer to try the demos!) http//www.rational.com/
  products/rose/index.jtmpl
• http//www.visible.com

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Unified Modeling Language

• Unified Modeling Language (UML) is an object
  oriented modeling language.
• UML is the culmination of the work of the three
  leading experts in the field - Grady Booch, Ivar
  Jacobson and James Rumbaugh. UML combined the
  best from ER diagrams, business modeling
  (workflow), object modeling and component
  modeling.
• Will be used in group projects

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UML Notation

• UML notation is useful for graphically depicting
  object oriented analysis and design models.
• Models system requirements
• Facilitates design decisions
• Promotes communications among key players
  involved in the development effort
• Integrates system views in a complete and
  consistent fashion
• Employs a simple notation set

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UML Example
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U M L S Y M B O L S
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Helpful tools for Diagramming

• RFFLow
• easy to use
• no limit time but number of symbols you can use
  is limited
• RFFLow - demo copy available at www.rff.com
• Tutorial is available at http//www.rff.com/tutori
  al.htm
• Samples are available at http//www.rff.com/sample
  s.htm
• Limited version available for demo (disallows new
  objects on a model after about 20 have been used)
• Smartdraw
• easy to use
• great collection of symbols
• 30 day free trial
• available at www.smartdraw.com

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Diagramming CASE Tool for OOAD

• Poseidon
• http//www.gentleware.com/
• http//www.gentleware.com/products/download.php3
• You must have the Java sdk installed on your
  machine
• http//java.sun.com/j2se/1.4.1/download.html
• Download the install anywhere version

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Poseidon

• Great tool to experiment with
• Community edition (the free one!) automatically
  generates C and HTML code
• Beware of its quirks!

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Quote of the Week

• "despite 50 years of progress, the software
  industry remains years perhaps decades short
  of the mature engineering discipline needed to
  meet the demands of an information age society."
  Scientific American, Sept 94