CASE Tools

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CASE Tools

• CIS 375
• Bruce R. Maxim
• UM-Dearborn

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CASE Tools

• Computer-Aided Software Engineering
• Prerequisites to tool use
• Need a collection of useful tools that help in
  every step of building a product
• Need an organized layout that enables tools to be
  found quickly and used efficiently
• Need a skilled craftsperson who understands how
  to use the tools effectively

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CASE Tools

• Upper CASE
• requirements
• specification
• planning
• design

• Lower CASE
• implementation
• integration
• maintenance

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CASE Building Blocks - 1

• CASE tools
• Integration framework
• specialized programs allowing CASE tools to
  communicate with one another
• Portability services
• allow CASE tools and their integration framework
  to migrate across different operating systems and
  hardware platforms without significant adaptive
  maintenance

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CASE Building Blocks - 2

• Operating system
• database and object management services
• Hardware platform
• Environmental architecture
• hardware and system support

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CASE Tool Taxonomy - 1

• Business process engineering tools
• represent business data objects, their
  relationships, and flow of the data objects
  between company business areas
• Process modeling and management tools
• represent key elements of processes and provide
  links to other tools that provide support to
  defined process activities
• Project planning tools
• used for cost and effort estimation, and project
  scheduling

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CASE Tool Taxonomy - 2

• Risk analysis tools
• help project managers build risk tables by
  providing detailed guidance in the identification
  and analysis of risks
• Requirements tracing tools
• provide systematic database-like approach to
  tracking requirement status beginning with
  specification

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CASE Tool Taxonomy - 3

• Metrics and management tools
• management oriented tools capture project
  specific metrics that provide an overall
  indication of productivity or quality,
  technically oriented metrics determine metrics
  that provide greater insight into the quality of
  design or code
• Documentation tools
• provide opportunities for improved productivity
  by reducing the amount of time needed to produce
  work products

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CASE Tool Taxonomy - 4

• System software tools
• network system software, object management
  services, distributed component support, and
  communications software
• Quality assurance tools
• metrics tools that audit source code to determine
  compliance with language standards or tools that
  extract metrics to project the quality of
  software being built

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CASE Tool Taxonomy - 5

• Database management tools
• RDMS and OODMS serve as the foundation for the
  establishment of the CASE repository
• Software configuration management tools
• uses the CASE repository to assist with all SCM
  tasks (identification, version control, change
  control, auditing, status accounting)
• Analysis and design tools
• enable the software engineer to create analysis
  and design models of the system to be built,
  perform consistency checking between models

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CASE Tool Taxonomy - 6

• PRO/SIM tools
• prototyping and simulation tools provide software
  engineers with ability to predict the behavior of
  real-time systems before they are built and the
  creation of interface mockups for customer review
• Interface design and development tools
• toolkits of interface components, often part
  environment with a GUI to allow rapid prototyping
  of user interface designs

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CASE Tool Taxonomy - 7

• Prototyping tools
• enable rapid definition of screen layouts, data
  design, and report generation
• Programming tools
• compilers, editors, debuggers, OO programming
  environments, fourth generation languages,
  graphical programming environments, applications
  generators, and database query generators
• Web development tools
• assist with the generation of web page text,
  graphics, forms, scripts, applets, etc.

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CASE Tool Taxonomy - 8

• Integration and testing tools
• data acquisition
• get data for testing
• static measurement
• analyze source code without using test cases
• dynamic measurement
• analyze source code during execution
• simulation
• simulate function of hardware and external
  devices
• test management
• cross-functional tools

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CASE Tool Taxonomy - 9

• Static analysis tools
• code-based testing tools, specialized testing
  languages, requirements-based testing tools
• Dynamic analysis tools
• intrusive tools modify source code by inserting
  probes to check path coverage, assertions, or
  execution flow
• non-intrusive tools use a separate hardware
  processor running in parallel with processor
  containing the program being tested

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CASE Tool Taxonomy - 10

• Test management tools
• coordinate regression testing, compare actual and
  expected output, conduct batch testing, and serve
  as generic test drivers
• Client/server testing tools
• exercise the GUI and network communications
  requirements for the client and server

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CASE Tool Taxonomy - 11

• Reengineering tools
• reverse engineering to specification tools
• generate analysis and design models from source
  code, where used lists, and other design
  information
• code restructuring and analysis tools
• analyze program syntax, generate control flow
  graph, and automatically generates a structured
  program
• on-line system reengineering tools
• used to modify on-line DBMS

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The next 17 slides come from Sommervilles book
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Requirements validation

• Concerned with demonstrating that the
  requirements define the system that the customer
  really wants
• Requirements error costs are high so validation
  is very important
• Fixing a requirements error after delivery may
  cost up to 100 times the cost of fixing an
  implementation error

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Requirements validation techniques

• Requirements reviews
• Systematic manual analysis of the requirements
• Prototyping
• Using an executable model of the system to check
  requirements.
• Test-case generation
• Developing tests for requirements to check
  testability
• Automated consistency analysis
• Checking the consistency of a structured
  requirements description

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Automated consistency checking
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Requirements management

• Requirements management is the process of
  managing changing requirements during the
  requirements engineering process and system
  development
• Requirements are inevitably incomplete and
  inconsistent
• New requirements emerge during the process as
  business needs change and a better understanding
  of the system is developed
• Different viewpoints have different requirements
  and these are often contradictory

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Requirements Change

• The priority of requirements from different
  viewpoints changes during the development process
• System customers may specify requirements from a
  business perspective that conflict with end-user
  requirements
• The business and technical environment of the
  system changes during its development

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Requirements evolution
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Requirements Management Planning

• During the requirements engineering process, you
  have to plan
• Requirements identification
• How requirements are individually identified
• A change management process
• Process followed when analysing a requirements
  change
• Traceability policies
• Amount of information about requirements
  relationships that is maintained
• CASE tool support
• Tool support required to manage requirements
  change

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Traceability

• Traceability is concerned with the relationships
  between requirements, their sources and the
  system design
• Source traceability
• Links from requirements to stakeholders who
  proposed these requirements
• Requirements traceability
• Links between dependent requirements
• Design traceability
• Links from the requirements to the design

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CASE tool support

• Requirements storage
• Requirements should be managed in a secure,
  managed data store
• Change management
• The process of change management is a workflow
  process whose stages can be defined and
  information flow between these stages partially
  automated
• Traceability management
• Automated retrieval of the links between
  requirements

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Requirements Change Management

• Should apply to all proposed changes to the
  requirements
• Principal stages
• Problem analysis.
• Discuss requirements problem and propose change
• Change analysis and costing.
• Assess effects of change on other requirements
• Change implementation.
• Modify requirements document and other documents
  to reflect change

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CASE Workbenches

• A coherent set of tools that is designed to
  support related software process activities such
  as analysis, design or testing
• Analysis and design workbenches support system
  modelling during both requirements engineering
  and system design
• These workbenches may support a specific design
  method or may provide support for a creating
  several different types of system models

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An analysis and design workbench
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Analysis workbench components

• Diagram editors
• Model analysis and checking tools
• Repository and associated query language
• Data dictionary
• Report definition and generation tools
• Forms definition tools
• Import/export translators
• Code generation tools

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Testing Workbenches

• Testing is an expensive process phase.
• Testing workbenches provide a range of tools to
  reduce the time required and total testing costs
• Most testing workbenches are open systems because
  testing needs are organization-specific
• Difficult to integrate testing with closed design
  and analysis workbenches

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Testing Workbench
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Testing Workbench Adaptation

• Scripts may be developed for user interface
  simulators and patterns for test data generators
• Test outputs may have to be prepared manually for
  comparison
• Special-purpose file comparators may be developed

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Integrated CASE Environments -1

• Provide mechanism for sharing information among
  all tools contained in the environment
• Enable changes to items to be tracked to other
  information items
• Provide version control and overall configuration
  management
• Allow direct access to any tool contained in the
  environment

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Integrated CASE Environments -2

• Establish automated support for the chosen
  software process model, integrating CASE tools
  and SCI's into a standard work break down
  structure
• Enable users of each tool to experience a
  consistent look and feel at the human-computer
  interface
• Support communication among software engineers
• Collect both management and technical metrics to
  improve the process and the product

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Integration Architecture - 1

• User Interface Layer
• interface toolkit
• contains software for UI management and library
  of display objects
• common presentation protocol
• guidelines that give all CASE tools the same look
  and feel (icons, mouse behavior, menu names,
  object names)
• Tools Layer
• tools management services
• control behavior of tools inside environment
• CASE tools themselves

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Integration Architecture - 2

• Object management layer (OML)
• performs the configuration management function,
  working with the CASE repository OML provides
  integration services
• Shared repository layer
• CASE database and access control functions
  enabling the OML to interact with the database

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CASE Repository Functions - 1

• Data integrity
• includes functions to validate entries to the
  repository and ensure consistency among related
  objects
• Information sharing
• provides mechanism for sharing information among
  multiple developers and multiple tools, controls
  modification of information
• Data-tool integration
• establishes shared data model and performs
  configuration management functions

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CASE Repository Functions - 2

• Data-data integration
• database management system allowing access to
  related objects so functions can be achieved
• Methodology enforcement
• E-R model used to define steps needed to be
  conducted to build the repository contents
• Document standardization
• definition of objects in the database leads
  directly to a standard approach for creation of
  engineering documents

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CASE Repository Content Summary

• Problem to be solved.
• Problem domain.
• Emerging solution.
• Rules pertaining to software process methodology.
• Project plan.
• Organizational content.

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DBMS Features Needed for CASE Repositories

• Non-redundant data storage
• High-level access
• Data independence
• Transaction control
• Ad hoc data queries and reports
• Openness
• Multi-user support

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CASE Repository Features - 1

• Storage of sophisticated data structures
• diagrams
• documents
• files
• simple variables
• information model describing relationships and
  semantics of data stored in repository

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CASE Repository Features - 2

• Integrity enforcement
• business rules
• policies, constraints
• requirements on the information being entered
  into repository, triggers may be used to check
  the validity of the design models in real time

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CASE Repository Features - 3

• Semantic-rich tool interface
• repository meta-model contains semantics that
  enable a variety of tools to interpret meaning of
  data stored in the repository
• Process/project management
• contains information about the software
  application
• characteristics of each project
• organization's general process for software
  development - phases, tasks, deliverables

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Configuration Management Features Need by CASE
Tools

• Versioning
• Dependency tracking and change management
• Requirements tracing
• Configuration management
• Audit trails

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The next 3 slides come from Sommervilles book
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CASE tools for Configuration Management

• Configuration management processes are
  standardized and involve applying pre-defined
  procedures
• Large amounts of data must be managed
• CASE tool support for configuration management is
  essential
• Mature CASE tools to support configuration
  management are available ranging from stand-alone
  tools to integrated workbenches

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Change Management Tools

• Change management is a procedural process so it
  can be modelled and integrated with a version
  management system
• Change management tools
• Form editor to support processing the change
  request forms
• Workflow system to define who does what and to
  automate information transfer
• Change database that manages change proposals and
  is linked to a VM system

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Version Management Tools

• Version and release identification
• Systems assign identifiers automatically when a
  new version is submitted to the system
• Storage management.
• System stores the differences between versions
  rather than all the version code
• Change history recording
• Record reasons for version creation
• Independent development
• Only one version at a time may be checked out for
  change. Parallel working on different versions