RAD and ARAD Barbara Tacchino
RAD and ARAD
Barbara Tacchino
Summary RAD (Rapid Application Development)
Definition and features Development cycle Team, tools, documentation, problems
ARAD (Architected Rapid Application Development) Definition and features The IBM ARAD solution: IBM Rational Rapid
Developer A business application scenario
What is RAD? Is a software development process model that
has been developed to respond to the need to deliver systems very fast
Actually it allows usable systems to be built in as little as 3-6 months
It has been developed in the early 1990s It takes inspiration from spiral model Its goals are: faster, better, cheaper
Problems addressed by RAD With conventional methods, there is a long delay
before the customer gets to see any results With conventional methods, there is nothing until
100% of the process is finished, then 100% of the software is delivered
With conventional methods, software development can take so long that the customer’s business has fundamentally changed by the time the system is ready for use
Satisfying the customer at the time of delivery
When use RAD?Project scope: focused, where the business objectives
are well defined and narrowProject data: already existProject decisions: can be made by a small number of
people who are available and co-locatedProject team: very small (six people)Project technical architecture: defined and clear and
the key technology components are well knownProject technical requirements: are reasonable and
well within the capability of the technology being usedIntensive involvement of the end user in the design of
the system (JAD, Joint Application Development)
Features of RAD Use of prototyping, which helps users visualize
and make adjustments to the system Use of a CASE repository to facilitate the re-
use of templates, components and systems Use of an integrated CASE toolset to generate
bug-free code from a fully validated design Development of a task structure that
encourages parallel project activities
RAD development cycle
RAD uses iterative prototyping JRP (Joint Requirement Planning) meeting: high-
level end-users and developers meet in a session to generate a list of initial requirements
Iteration Designers review the prototype Developers build/evolve the prototype based on
current requirements Customers try out the prototype and evolve their
requirements Focus Group Meeting (JAD): customers and developers
meet to review product together and refine requirements
Requirements and change requests are “timeboxed”
Stages of RAD: Requirements Planning takes one to four weeks to complete is defined during a JRP meeting consists of a review of the areas immediately
associated with the proposed system produces a broad definition of the system requirements
in terms of the functions the system will support deliverables from this stage include
an outline system area model (entity and process model)
a definition of the system’s scope a cost justification for the new system
Stages of RAD: User Design is defined during JAD meetings consists of a detailed analysis of the business
activities related to the proposed system to outline the design
The team defines entity types and creates action diagrams defining the interactions between processes and data
System procedures are designed and preliminary layouts of screens are developed
Prototypes of critical procedures are built A plan for implementing the system is prepared
Together with the next stage, User Design consists of a series of iterations
Stages of RAD: Construction Developers, working directly with users, finalize
the design, build and test the prototype The deliverables include documentation and
instructions necessary to operate the new application and procedures needed to put the system into operation
Timebox and parallel development: involves monitoring progresses to complete each task quickly
The prototype is reviewed by users Requirements document can be modified, so another
iteration starts
Stages of RAD: Transition the period during which the newly developed
system gradually replaces existing systems User acceptance: end of iterations Developers train users to operate the new
application objectives
Install the system in production operation with minimal disruption of normal business activity
Maximize the effectiveness of the system in supporting the intended business activities
Identify potential future enhancements
RAD team should include both developers and users of the system
and each person can play several rolesUser Coordinator: appointed by the Sponsor to oversee the
project from the user perspectiveRequirements Planning Team: high-level users
participating in the requirements planningUser Design Team: participates in the design meetingsUser Review Board: review the system after the
construction and decide if modifications are neededTraining Manager: responsible for training users to work
with the new systemProject Manager: oversees the development effortConstruction (SWAT) Team: two to six developers highly
trained to work together at high speed. SWAT stands for “Skilled Workers with Advanced Tools”. This team builds the system and also participate in the design meetings
Meeting Leader: organizes and conducts the meetings
RAD tools RAD depends entirely on automated tools
CASE software provides planning, analysis and design “workbenches” that are fully integrated so that one tool directly employs the information from another
repository stores the knowledge from the multiple tools in an integrated manner
code generator is fully integrated with the design toolset and allows the developer to design, modify, generate code and test as quickly as possible
RAD documentation Customers, developers and management must
accept informal deliverables Notes from user meetings rather than formal
requirements documents Notes from designers meetings rather than formal
design documents Principle: create the minimum documentation
necessary to facilitate future development and maintenance
Problems of RAD criticized because it lacks a methodology and
a designed architecture flexibility of RAD systems decreases as
applications grow RAD tends to fail when
Application must interoperate with existing programs Performance and reliability are critical The system cannot be modularized New technologies are used
Introduction to ARAD IBM acquired Rational Software Starting point: RUP (Rational Unified Process)
It is a software development process model which includes a lot of features of the spiral model (iteration, prototyping, phased development)
Each phase is supported by visual tools It establishes four phases of development, each
consisting of one ore more executable iterations
What is Architected RAD? an evolution of RAD which supports the creation
of enterprise applications and has a “formal” process
a version of the Rational Unified Process (RUP) that has been optimized for RAD
the team is made up of eleven people: a project leader, one analyst, eight developers and one technology architect
is characterized by a unified process business modeling with UML rapid application development
Unified ARAD process One problem of RAD is that it lacks a “formal”
process Unified ARAD process unifies the team by
providing roadmaps for application development that include defining flows, stakeholders and explaining how they interrelate
Business modeling with UML RAD lacks a focus on the business processes
that drive software requirements ARAD focuses on business modeling
analysts can use UML to analyze business requirements, define business use cases, define the information model for the application and the business processes and business rules
The IBM ARAD solution: IBM Rational Rapid Developer is the new Rational software solution for ARAD (2003) provides an integrated application development
environment and process that unifies team skills supports rapid application development, integration and
architected code construction helps team rapidly deliver n-tier business applications
without encountering the complexity of the underlying technology platforms
enables late binding of construction patterns and deployment platforms
integrates with the IBM Rational lifecycle toolset covers the complete lifecycle, from requirements to
deployment supports parallel development, version management and
change management
IBM Rational Rapid Developer workflow Rational Rapid Developer follows a
model-driven approach to application development
Nine out of ten members of the development team are focused on business process
Development team begins by capturing requirements and assessing existing assets (or requiring new ones) to support the process
IBM Rational Rapid Developer workflow (2) The next step focuses
on visual modeling the application and designing Web, wireless, XML, messaging and Web services transactions
Rational Rapid Developer provides essential UML models
IBM Rational Rapid Developer workflow (3) The application,
completely visually modeled, resides in the application repository before it is cast into a chosen technology platform
IBM Rational Rapid Developer workflow (4) Now the technology
expert decides how the application will be constructed and deployed choosing the platform and determining patterns
IBM Rational Rapid Developer workflow (5) Based on choices by the
team's technical expert, Rational Rapid Developer automatically constructs the final application in a matter of minutes, and even automatically compiles, test and deploys it
Each stage can be iterated
Users involvement
A business application scenario
Let’s use the ARAD process to design this marketplace application
Business requirements with UML Use cases that describe the Web, wireless and
integration functions of the application IBM Rational Rapid Developer provides a
project estimator that can estimate the work effort required to develop the application, based on these use cases
Model visually the application: use some of the UML models such as UML Class Model
Business requirements with UML (2) Import legacy database models: the database schema is
automatically converted into an XML file and imported into Rational Rapid Developer as a class model
Rational Rapid Developer can perform object-to-relational mapping and create database schema for relational databases
Define business rules using a Java business rule editor. Rule examples are: inventory check, order pricing, customer credit check
Define business processes as state chart/activity diagrams
They are purely analytical and do not lead to any direct code construction
Develop user interfaces rapidly Define site flow models for each actor of the
application: these models reflect the user interface use cases
Define the look and feel of the application with styles and themes
Design Web pages: it is visual and rapid and facilitated by the Page Architect feature
Develop user interfaces rapidly (2) Design page logic: it is written in Java using
the Logic Architect IBM Rational Rapid Developer provides nearly 100
code templates, so developers need only fill in parameters to write code
IBM Rational Rapid Developer automatically construct, compiles and deploys the application
Internationalization of pages: a translation file is created and imported
Rapid integration development Enterprise integration with XML Integration with Web Services: IBM Rational
Rapid Developer discovers the services published in a public repository, than the developer clicks on a service and a service call is inserted in the code like a Java method call
The developer specifies only the method call parameters
IBM Rational Rapid Developer will automatically handle all the mechanics of invoking the service, using SOAP request/ response mechanism
N-tier architected deployment The technology architect can deploy the same
application in varying environments. Chosen a particular environment, the architect select
appropriate technologies and fine tunes the construction patterns
The desired degree of performance, scalability and security can be specified
IBM Rational Rapid Developer creates an optimized code for each deployment model
IBM Rational Rapid Developer can now be used for functional and performance testing
Each stage can be iterated
Deployment models
Rational toolset In addition to IBM Rational Rapid Developer
($6,595) IBM Rational RequisitePro® ($2,034) IBM Rational XDE ($1,595) IBM Rational Rose IBM Rational ClearCase® ($65,950 for a 10-user
license) IBM Rational ClearQuest® IBM Rational TeamTest®
References RAD
www.gantthead.com/process/processMain.cfm?ID=2-19516-2
sysdev.ucdavis.edu/WEBADM/document/rad_toc.htm
ARAD www.ibm.com www-106.ibm.com/developerworks/rational/library/
441.html#N10269