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LESSON 27
Object Oriented Analysis and Design
There are some terms important to explaining the concept object oriented analysis and design.
26.1 Object
An object can be defined as "A concept, abstraction, or thing with crisp boundaries and meaning of the
problem at hand. Objects serve two purposes, they promote understanding of the real world and provide a
practical basis for computer implementation."
Rumbaugh et al. (1991)
26.2 Classes
A class is defined as "The purpose of a class is to specify a classification of objects and to specify the
features that characterize the structure and behavior of those objects."
Attributes & Methods
Attributes are the characteristics of object / class and methods are the operations related to the object /
class.
In order to explain concepts of Class, Object, Attribute, Method, etc, let's consider an example. A company
may be interested in creating a database for better customer relationships. For this purpose the company
may plan to create a database in the following manner.
Example
Class
Customers
Object/Instance
A particular customer
Attribute
Name, Address, etc.
(Characteristics of the
object)
Methods (Operations Add, update, delete,
related to the objects) validate, etc.
26.3 Inheritance
Inheritance is usually identified by the phrase "is a kind of." For example, the term "automobile " is a
generalization of "van", "car", "truck", and many others. Conversely, we can say that since cars are
automobiles so they inherit all the properties common to all the automobiles e.g. engine, steering, etc. but
capacity and type of engine, size of steering will be different from each class, based on these differences
sub-classes are created. Two concepts are used in relation to inheritance; generalization and specialization.
Classification is hierarchical in nature, a vehicle may be classified as truck or car, a car may further be Sub-
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classified as hatchback or sedan or sports or SUV. Moving up the hierarchy is terms as generalization and
down the hierarchy is referred to as specialization.
More general
(Classes)
Vehicle
Truck
Car
Sedan
Sports
More specialized
(subclasses)
A real customer such as "ABC Company" is an object/instance of the class of customers. If you have
different kinds of customers, such as domestic, commercial and industrial, you can create three new classes
of customers that are derived from of the Customer class. These derived classes use inheritance to gain
access to all of the common customer class attributes and methods. Special attributes which are unique to
each class can also be defined.
Message-Passing
Several objects may collaborate to fulfil each system action. For example, "Record CD sale" is a process,
which could involve a CD stock item, a sales transaction, a sales assistant, etc. These objects involved in the
process of CD sale communicate by sending each other message.
26.4 Encapsulation
Encapsulation means information hiding. For instance, when the Play Button is pressed, the tape is played.
However the actual process of how the tape is played is not visible. Another example can be given of
banking software. The banking software contains an option of computation of profit, when the option is
activated the amount is computed as and when required, however, the actual steps when performed remain
invisible to the user.
26.5 Polymorphism
Following example will help understand the concept in a better manner.
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Message from another
`Layers of an onion'
object requests a service.
model of an object:
Operation called only via valid
operation signature.
An outer layer of
operation signatures...
Data accessed only by
object's own operations.
...gives access to middle
layer of operations...
An object's data
is hidden
...which can access
(encapsulated).
inner core of data
Hence based on the example given above, the concept can be defined. Ppolymorphism is a derived from
Greek language meaning "having multiple forms"). Polymorphism is the characteristic of being able to
assign a different meaning or usage to something in different contexts - specifically, to allow an entity such
as a variable, a method, or an object to have more than one form.
26.6 What is Business Process Reengineering?
"Reengineering is the fundamental rethinking and redesign of business processes to achieve dramatic
improvements in critical, contemporary measures of performance, such as cost, quality, service and speed."
(Hammer & Champy, 1993)
The focus of this technique or method is to smooth the procedures and approaches undertaken by various
departments of an organization to achieve their respective objectives. The term rethinking refers to the idea
of firstly studying and then analyzing all or any of the processes to any extent depending on the need and
objective of change. The objectives to be achieved according to this definition are to qualitatively enhance
the efficiency and quality of delivery and production of goods and services. to achieve qualitative
improvement in the handling of production, procedural and customer related matters.
The concept of business process reengineering can be understood in the following manner.
"The analysis and design of workflow and processes within and between organizations"
(Davenport and Short, 1990).
The definition adds another aspect to the definition. It extends the concept of BPR by studying the links of
various procedures used by and between organizations. A number of processes undertaken within the
organization may have links with external organizations either as input or output. For example, raw material
purchases from suppliers are an integral part of planning, production and sales. Hence making the supplier
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more efficient to deliver on time becomes critical, industrial customers placing regular huge volume orders
in accordance with theirs own plans. You as the supplier need this information to input into your own
planning.
Competitive Advantage
One of the main goals of introducing BPR is to provide a competitive edge to the business and that can
only be achieved by providing a better product in a timely fashion to the customers in accordance with their
needs.
For Example, a petroleum company might be faced with issues such as, the product is being tampered with
before delivery to points of sale, and the gasoline is not being delivered on time to the points of sale, the
issues to be dealt at the dealer-owned-petrol pumps. Question: Why should it be worried, if at all?
The company may after the process review resolve the above stated issues such as redefining the design of
the containers/tanker, installing tracking devices on the delivery vehicles, setting up Company owned points
of sale, eliminating storage depots and ensuring timely direct deliveries to POS, etc.
While use of BPR helps an organization in gaining competitive advantage in the use of processes,
effectiveness and efficiency should also be kept in mind.
Effectiveness
By effectiveness, it is meant that how effective is the manner in which the product or service is offered to
the customer? This may include packaging, advertising, creating customer loyalty, timely availability in the
market, understanding customer needs & requirements related to the particular product or service being
offered.
Efficiency
The concept relates to not only how efficiently a quality product is manufactured, packed, stored and
delivered to customers/points of sale but also how quickly are customer complaints responded to, in what
manner are they removed, what is the cost of not doing so as to be compared to the cost of not doing so,
and how it can be made more efficient. Efficiency is not just about being efficient at the production floor
level but the decision making at management level also has to be efficient. Customer might not be able to
see all of the process but he can see the efficiency coming out of it.
Major steps in BPR
Senior managers may begin the task of process alignment by a series of BPR steps. These steps develop a
self-reinforcing cycle of commitment, communication, and culture change. The steps may include gaining
commitment to change through the formulation of the top team, developing a shared vision and mission of
the business and of what change is required, defining the measurable objectives, which must be agreed by
the team, as being the quantifiable indicators of success in terms of the mission, identify the Critical Success
Factors (CSF's) based on the mission of the organization.
Following steps should be followed to implement BPR.
 Break down the CSF's into the key or critical business processes and gain process ownership.
 Break down the critical processes into sub-processes, activities and task and form the teams
around these.
 Re-design, monitor and adjust the process-alignment in response to difficulties in the change
process.
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Table of Contents:
  1. Need for information, Sources of Information: Primary, Secondary, Tertiary Sources
  2. Data vs. Information, Information Quality Checklist
  3. Size of the Organization and Information Requirements
  4. Hierarchical organization, Organizational Structure, Culture of the Organization
  5. Elements of Environment: Legal, Economic, Social, Technological, Corporate social responsibility, Ethics
  6. Manual Vs Computerised Information Systems, Emerging Digital Firms
  7. Open-Loop System, Closed Loop System, Open Systems, Closed Systems, Level of Planning
  8. Components of a system, Types of Systems, Attributes of an IS/CBIS
  9. Infrastructure: Transaction Processing System, Management Information System
  10. Support Systems: Office Automation Systems, Decision Support Systems, Types of DSS
  11. Data Mart: Online Analytical Processing (OLAP), Types of Models Used in DSS
  12. Organizational Information Systems, Marketing Information Systems, Key CRM Tasks
  13. Manufacturing Information System, Inventory Sub System, Production Sub System, Quality Sub system
  14. Accounting & Financial Information Systems, Human Resource Information Systems
  15. Decision Making: Types of Problems, Type of Decisions
  16. Phases of decision-making: Intelligence Phase, Design Phase, Choice Phase, Implementation Phase
  17. Planning for System Development: Models Used for and Types of System Development Life-Cycle
  18. Project lifecycle vs. SDLC, Costs of Proposed System, Classic lifecycle Model
  19. Entity Relationship Diagram (ERD), Design of the information flow, data base, User Interface
  20. Incremental Model: Evaluation, Incremental vs. Iterative
  21. Spiral Model: Determine Objectives, Alternatives and Constraints, Prototyping
  22. System Analysis: Systems Analyst, System Design, Designing user interface
  23. System Analysis & Design Methods, Structured Analysis and Design, Flow Chart
  24. Symbols used for flow charts: Good Practices, Data Flow Diagram
  25. Rules for DFDs: Entity Relationship Diagram
  26. Symbols: Object-Orientation, Object Oriented Analysis
  27. Object Oriented Analysis and Design: Object, Classes, Inheritance, Encapsulation, Polymorphism
  28. Critical Success Factors (CSF): CSF vs. Key Performance Indicator, Centralized vs. Distributed Processing
  29. Security of Information System: Security Issues, Objective, Scope, Policy, Program
  30. Threat Identification: Types of Threats, Control Analysis, Impact analysis, Occurrence of threat
  31. Control Adjustment: cost effective Security, Roles & Responsibility, Report Preparation
  32. Physical vs. Logical access, Viruses, Sources of Transmissions, Technical controls
  33. Antivirus software: Scanners, Active monitors, Behavior blockers, Logical intrusion, Best Password practices, Firewall
  34. Types of Controls: Access Controls, Cryptography, Biometrics
  35. Audit trails and logs: Audit trails and types of errors, IS audit, Parameters of IS audit
  36. Risk Management: Phases, focal Point, System Characterization, Vulnerability Assessment
  37. Control Analysis: Likelihood Determination, Impact Analysis, Risk Determination, Results Documentation
  38. Risk Management: Business Continuity Planning, Components, Phases of BCP, Business Impact Analysis (BIA)
  39. Web Security: Passive attacks, Active Attacks, Methods to avoid internet attacks
  40. Internet Security Controls, Firewall Security SystemsIntrusion Detection Systems, Components of IDS, Digital Certificates
  41. Commerce vs. E-Business, Business to Consumer (B2C), Electronic Data Interchange (EDI), E-Government
  42. Supply Chain Management: Integrating systems, Methods, Using SCM Software
  43. Using ERP Software, Evolution of ERP, Business Objectives and IT
  44. ERP & E-commerce, ERP & CRM, ERP Ownership and sponsor ship
  45. Ethics in IS: Threats to Privacy, Electronic Surveillance, Data Profiling, TRIPS, Workplace Monitoring