Modern Systems Analysis and Design Seventh Edition Jeffrey A.

Modern Systems Analysis and Design Seventh Edition Jeffrey A. Hoffer Joey F. George Joseph S. Valacich Chapter 1 The Systems Development Environment

Learning Objectives Define information systems analysis and design. Describe the information systems development life cycle (SDLC). Explain Rapid Application Development (RAD) and computer-aided software engineering (CASE) tools. Describe Agile Methodologies and eXtreme Programming. Explain object-oriented analysis and design and the Rational Unified Process (RUP). Chapter 1 Copyright 2014 Pearson Education, Inc. Publishing as Prentice Hall 2

Introduction Information Systems Analysis and Design Complex organizational process Used to develop and maintain computerbased information systems Used by a team of business and systems professionals Chapter 1 Copyright 2014 Pearson Education, Inc. Publishing as Prentice Hall 3

Introduction (Cont.) FIGURE 1-1 An organizational approach to systems analysis and design is driven by methodologies, techniques, and tools Chapter 1 Copyright 2014 Pearson Education, Inc. Publishing as Prentice Hall 4

Introduction (Cont.) Application Software Computer software designed to support organizational functions or processes Systems Analyst Organizational role most responsible for analysis and design of information systems Chapter 1 Copyright 2014 Pearson Education, Inc. Publishing as Prentice Hall 5

A Modern Approach to Systems Analysis and Design 1950s: focus on efficient automation of existing processes 1960s: advent of procedural third generation languages (3GL) faster and more reliable computers 1970s: system development becomes more like an engineering discipline Chapter 1 Copyright 2014 Pearson Education, Inc. Publishing as Prentice Hall 6

A Modern Approach to Systems Analysis and Design (Cont.) 1980s: major breakthrough with 4GL, CASE tools, object-oriented methods 1990s: focus on system integration, GUI applications, client/server platforms, Internet The new century: Web application development, wireless PDAs and smart phones, component-based applications, application service providers (ASP) Chapter 1 Copyright 2014 Pearson Education, Inc. Publishing as Prentice Hall 7

Developing Information Systems System Development Methodology is a standard process followed in an organization to conduct all the steps necessary to analyze, design, implement, and maintain information systems. Chapter 1 Copyright 2014 Pearson Education, Inc. Publishing as Prentice Hall 8

Systems Development Life Cycle (SDLC) Traditional methodology used to develop, maintain, and replace information systems Phases in SDLC: Planning Analysis Design Implementation Maintenance Chapter 1 Copyright 2014 Pearson Education, Inc. Publishing as Prentice Hall 9

Standard and Evolutionary Views of SDLC FIGURE 1-2 Systems development life cycle Chapter 1 FIGURE 1-3 Evolutionary model Copyright 2014 Pearson Education, Inc. Publishing as Prentice Hall 10

Systems Development Life Cycle (SDLC) (Cont.) Planning – an organization’s total information system needs are identified, analyzed, prioritized, and arranged Analysis – system requirements are studied and structured Design – a description of the recommended solution is converted into logical and then physical system specifications Chapter 1 Copyright 2014 Pearson Education, Inc. Publishing as Prentice Hall 11

Systems Development Life Cycle (SDLC) (Cont.) Logical design – all functional features of the system chosen for development in analysis are described independently of any computer platform Physical design – the logical specifications of the system from logical design are transformed into the technology-specific details from which all programming and system construction can be accomplished Chapter 1 Copyright 2014 Pearson Education, Inc. Publishing as Prentice Hall 12

Systems Development Life Cycle (SDLC) (Cont.) Implementation – the information system is coded, tested, installed and supported in the organization Maintenance – an information system is systematically repaired and improved Chapter 1 Copyright 2014 Pearson Education, Inc. Publishing as Prentice Hall 13

Chapter 1 Copyright 2014 Pearson Education, Inc. Publishing as Prentice Hall 14

The Heart of the Systems Development Process FIGURE 1-8 Analysis–design–code–test loop FIGURE 1-9 The heart of systems development Current practice combines analysis, design, and implementation into a single iterative and parallel process of activities. Chapter 1 Copyright 2014 Pearson Education, Inc. Publishing as Prentice Hall

Traditional Waterfall SDLC One phase begins when another completes, with little backtracking and looping. FIGURE 1-10 Traditional waterfall SDLC Chapter 1 Copyright 2014 Pearson Education, Inc. Publishing as Prentice Hall 16

Problems with Waterfall Approach Feedback ignored, milestones lock in design specs even when conditions change Limited user involvement (only in requirements phase) Too much focus on milestone deadlines of SDLC phases to the detriment of sound development practices Chapter 1 Copyright 2014 Pearson Education, Inc. Publishing as Prentice Hall 17

Different Approaches to Improving Development CASE Tools Rapid Application Development (RAD) Agile Methodologies eXtreme Programming Chapter 1 Copyright 2014 Pearson Education, Inc. Publishing as Prentice Hall 18

Computer-Aided Software Engineering (CASE) Tools Diagramming tools enable graphical representation. Computer displays and report generators help prototype how systems “look and feel”. IBM’s Rational products are the best known CASE tools. Chapter 1 Copyright 2014 Pearson Education, Inc. Publishing as Prentice Hall 19

Computer-Aided Software Engineering (CASE) Tools (Cont.) Analysis tools automatically check for consistency in diagrams, forms, and reports. A central repository provides integrated storage of diagrams, reports, and project management specifications. Chapter 1 Copyright 2014 Pearson Education, Inc. Publishing as Prentice Hall 20

Computer-Aided Software Engineering (CASE) Tools (Cont.) Documentation generators standardize technical and user documentation. Code generators enable automatic generation of programs and database code directly from design documents, diagrams, forms, and reports. Chapter 1 Copyright 2014 Pearson Education, Inc. Publishing as Prentice Hall 21

CASE Tools (Cont.) FIGURE 1-11 Screen shot of ArgoUML, an open source CASE tool (Source: http://argouml.tigris.org/) Chapter 1 Copyright 2014 Pearson Education, Inc. Publishing as Prentice Hall 22

CASE Tools (Cont.) Chapter 1 Copyright 2014 Pearson Education, Inc. Publishing as Prentice Hall 23

Rapid Application Development (RAD) Decreases design and implementation time Involves: extensive user involvement, prototyping, integrated CASE tools, code generators More focus on user interface and system function, less on detailed business analysis and system performance Chapter 1 Copyright 2014 Pearson Education, Inc. Publishing as Prentice Hall 24

Rapid Application Development (RAD) (Cont.) FIGURE 1-12 RAD life cycle Chapter 1 Copyright 2014 Pearson Education, Inc. Publishing as Prentice Hall 25

Agile Methodologies Motivated by recognition of software development as fluid, unpredictable, and dynamic Three key principles Adaptive rather than predictive Emphasize people rather than roles Self-adaptive processes Chapter 1 Copyright 2014 Pearson Education, Inc. Publishing as Prentice Hall 26

The Agile Methodologies group argues that software development methodologies adapted from engineering generally do not fit with realworld software development. Chapter 1 Copyright 2014 Pearson Education, Inc. Publishing as Prentice Hall 27

When to use Agile Methodologies If your project involves: Unpredictable or dynamic requirements Responsible and motivated developers Customers who understand the process and will get involved Chapter 1 Copyright 2014 Pearson Education, Inc. Publishing as Prentice Hall 28

Chapter 1 Copyright 2014 Pearson Education, Inc. Publishing as Prentice Hall 29

eXtreme Programming Short, incremental development cycles Automated tests Two-person programming teams Coding, testing, listening, designing Chapter 1 Copyright 2014 Pearson Education, Inc. Publishing as Prentice Hall 30

eXtreme Programming (Cont.) Coding and testing operate together Advantages: Communication between developers High level of productivity High-quality code Chapter 1 Copyright 2014 Pearson Education, Inc. Publishing as Prentice Hall 31

Object-Oriented Analysis and Design (OOAD) Based on objects rather than data or processes Object: a structure encapsulating attributes and behaviors of a realworld entity Chapter 1 Copyright 2014 Pearson Education, Inc. Publishing as Prentice Hall 32

Object-Oriented Analysis and Design (OOAD) (Cont.) Object class: a logical grouping of objects sharing the same attributes and behaviors Inheritance: hierarchical arrangement of classes enable subclasses to inherit properties of superclasses Chapter 1 Copyright 2014 Pearson Education, Inc. Publishing as Prentice Hall 33

Rational Unified Process (RUP) An object-oriented systems development methodology Establishes four phase of development: inception, elaboration, construction, and transition Each phase is organized into a number of separate iterations. Chapter 1 Copyright 2014 Pearson Education, Inc. Publishing as Prentice Hall 34

FIGURE 1-13 Phases of OOSAD-based development Chapter 1 Copyright 2014 Pearson Education, Inc. Publishing as Prentice Hall 35

Our Approach to Systems Development The SDLC is an organizing and guiding principle in this book. We may construct artificial boundaries or artificially separate activities and processes for learning purposes. Our intent is to help you understand all the pieces and how to assemble them. Chapter 1 Copyright 2014 Pearson Education, Inc. Publishing as Prentice Hall 36

Summary In this chapter you learned how to: Define information systems analysis and design. Describe the information Systems Development Life Cycle (SDLC). Explain Rapid Application Development (RAD), prototyping, Computer Aided Software Engineering (CASE), and Service-Oriented Architecture (SOA). Describe agile methodologies and eXtreme programming. Explain Object-Oriented Analysis and Design (OOAD) and the Rational Unified Process (RUP). Chapter 1 Copyright 2014 Pearson Education, Inc. Publishing as Prentice Hall 37

Copyright 2014 Pearson Education, Inc. Publishing as Prentice Hall