MIS SPPU Unit II

1. RAD
• RAD is high speed adaptation of Water fall model
• Requirement should be understood very well
• Business modeling->Data Modeling-> Process Modeling-> Application
generation-> Testing and turnover
• The system is broken into smaller and relatively independent
components.
• These components are developed using step 3
• Automation further helps in code generation
• Time box approach suggest that delivery is important even if some of
the features are compromised

2. CASE
• CASE tool helps in developing information system in all the phases of
SDLC.
• Automated tools improve speed and quality
• Assist software engineering in every phase of s/w development
• E.g.
• MS project
• Project Analyst
• Oracle 9i designer

3. Advantages
• Improve productivity, automation, standardization, reduce cost,
speed, auto code generation and error checking, reusability
• Disadvantage; flexibility, may not always fulfill requirement

4. CASE TOOLS
• Diagramming tools
• Screens and report generators
• Analysis tools
• Tools repository
• Documentation generator
• Code generators

5. Continue..
• Analysis and design tools: help in creating data flow diagrams,
structure charts
• Data modelling tools: help in maintaining data dictionary, ER diagrams
• Prototyping tools: help in creating screens, menus , report layouts
• Coding tools
• Testing tools: like online debugging facilities

6. Upper and Lower Case tools
• UPPER CASE (FRONT END)
• Emphasize data modeling (defining objects related to business) and
logical design
• LOWER CASE (BACK END)
• Emphasize code generation and physical design
• Requirement analysis design specification of SDLC are upper case
tools
• Coding and implementation related tools are lower case/

7. Architecture
• User Interface Layer
• Tools layer: it has tool management service. It helps in execution
(use) of one or more tools required by user.
• Object Management layer: It acts for integration of tool layer with
Shared repository layer
• Shared repository layer: It define CASE data base and access control
functions ( i.e. who can access CASE)

8. OOPS
• Programming language model organized around objects rather than
actions.
• Historically program has been viewed as a logical procedure that
takes input data, processes it and produces output data.Hence,
challenge was to write logic
• In Oo systems everything is considered as object. Object possesses
individual characteristics and methods. Information system is viewed
as collection of objects that work together to accomplish task
• Object is an entity, may be real/abstract; a thing in the computer
system that can respond to messages

9. • Object possesses properties/ attributes
• It also possesses methods/functions
• Thus in OOS objects are designed instead of processes. This ensures reusability of
objects
• First a class is created with data and functions
• Object is an instance (example ) of class
• E.g a object student is created
• With data name /DOB
• Functions: Total marks/ Average Percentage/Fees status
• Amit will be one object and Rahul will be another for class student
• Now accountant can use object to find fees due and professor can use it to find
result

10. Characteristics
• Inheritance: From Class student new class could be created. E.g.
overall student performance a new class inheriting all characteristics
of class student.
• Abstraction: one will deal with classes without requiring to know
about background details
• Encapsulation: storing data and function in single unit is
encapsulation
• Polymorphism: Ability to take more than one form.