Systems Development Life Cycle (SDLC), Methodologies and the Unified Process

Question 1

Why do we need a formal process?

Answer 1

• Failures occur (too) often
• Creating systems is not intuitive
• Projects are late, over budget or delivered with fewer features than planned
• Designed systems can be focused to deliver business value

Question 2

What is SDLC and its sequential activities?

Answer 2

System Development Life Cycle.

Planing , Analysis, Designing, Implementing.

Question 3

Planning - Why should we build the system?

Answer 3

Project Initiation-> Project management

Question 4

Analysis - What should the
system do? Where
and when will it be used?

Answer 4

Analyse - Develop Analysis Strategy -> Gather Requirements -> Develop Proposal

Question 5

Design - How will the system be built?

Answer 5

Design - Develop Design -> Develop Architecture -> Design Databases & Files -> Design Programs

Question 6

Implementation - Build the system

Answer 6

Implement - Contract -> Install -> Support

Question 7

What is a methodology?

Answer 7

A methodology is a formalized approach to implement a system.

Question 8

Types of Methodology?

Answer 8

• Structured Design
• Rapid Application Development
• Agile Development

Question 9

Mention the types of Structured Design methodologies

Answer 9

• Waterfall Development

- Parallel Development

Question 10

Mention the types of Rapid Application Development methodologies

Answer 10

• Phased
• Prototyping
• Throwaway Prototyping

Question 11

Mention the types of Agile Development methodologies

Answer 11

• eXtreme Programming
• SCRUM
• TDD

Question 12

What is the OO paradigm?

Answer 12

• Introduction of event-driven programs
• Introduction of GUI
• Increasing complexity, cost of programming
• Driver for better linkage between process and computer program

Question 13

What is OOAD?

Answer 13

Object-Oriented Analysis and Design is Use-Case driven, architecture-centric, iterative and incremental

Question 14

What is Use-case driven?

Answer 14

• A use-case describes a single business process

- Use-case define the behavior of a system

Question 15

Describe the views of architecture centric?

Answer 15

• [External] Functional view: focuses on the user’s perspective
• [Structural] Static view: focuses on attributes, methods, classes and relationships
• [Behavioral] Dynamic view: focuses on messages between classes and resulting behaviors

Question 16

What are the OOAD benefits?

Answer 16

• Code reuse and recycling: Objects created for OO programs can be reused in other programs
• Encapsulation: objects can hide certain parts of themselves from programmers preventing them from tampering with values they shouldn’t
• Desing benefits: OO programs force designers to go trough an extensive planning phase, which makes for better design with fewer flaws.
• Software maintenance: OO programs are easier to modify and maintain than non-OO programs

Question 17

What are the OOAD criticisms?

Answer 17

• OOP not really reusable and modular
• Emphasizes design and modeling at the expense of algorithm
• No significant difference in productivity between OOP and procedural

Question 18

What comprises the unified process?

Answer 18

Unified process is a specific methodology for OO analysis and design.

• 4 phases that describe how the system evolves over time (Inception/Elaboration/Construction/Transition)
• 7 engineering workflows that describe collections of tasks that occur throughout the lifecycle
• 5 support workflows that describe disciplines needed to ensure consistency of approach and method

Question 19

What is UML?

Answer 19

UML is the unified modelling language to describe the unified process. This provides a common vocabulary object-oriented terms and diagramming techniques to model any system development project from analysis through implementation.

UML uses Structural and behavior diagrams

UML doesn’t include staffing, budgeting, contract management, maintenance, operation, support.

Question 20

OOP Languages

Answer 20

Most widely used programming languages are multi-paradigm that support OOP such as Java, Python, C++, C#, PHP.

Question 21

What are classes and objects?

Answer 21

• Object (instance): instantiation of a class
• Attributes: information that describes the class
• State: describes its values and relationships at a point in time

Question 22

What are methods and messages?

Answer 22

• Methods: behavior of a class

- Messages: information sent to an object to a trigger a method.