MIS 307 - Chapter 1 - The System Development Environment

types of CASE Tools

-diagramming tools enable systems data to be represented graphically -analysis tools auto check for errors in diagrams, forms, and reports -code generators enable to auto generation of program and database definition code from design docs, diagrams, forms, and reports

The 1980s also included:

-off the shelf software -4th gen languages

SDLC

1. Planning 2. Analysis 3. Design 4. Implementation 5. Maintenance

three key principles of Agile methodologies

1. focus on adaptive rather than predictive methodologies 2. focus on people rather than roles 3. focus on self-adaptive processes

the relevant parts of eXtreme programming that relate to design specifications are:

1. how planning, analysis, design, and construction are all fused into a single phase of activity 2. unique way of capturing and presenting system requirements and design specs

RUP has 4 phases:

1. inception 2. elaboration 3. construction 4. transition

What three elements work together to form an organizational approach to systems analysis and design?

1. methodologies 2. tools 3. techniques

advantages of paid (two-person) programming:

1. more (and better) communication 2. higher levels of productivity 3. higher-quality code 4. reinforcement of the other practices in eXtreme programming such as the code-and-test discipline

Fowler recommends agile/adaptive processes if your project involves:

1. unpredictable or dynamic requirements 2. responsible and motivated devs 3. customers who understand the process and will get involved

two key emphases of eXtreme programming:

1. use of two-person programming teams 2. having a customer on-site during the dev process

Agile Methodologies

A family of development methodologies characterized by short iterative cycles and extensive testing; active involvement of users for establishing, prioritizing, and verifying requirements; and a focus on small teams of talented, experienced programmers.

RUP

Rational Unified Process

object-oriented analysis and design

Systems development methodologies and techniques based on objects rather than data or processes.

What can the SDLC be thought of as?

a circular process in which the end of the useful life of one system leads to the beginning of another project that will develop a new version or replace an existing system altogether

the output of the analysis phase is

a description of (but not a detailed design for) the alternative solution recommended by the analysis team

With eXtreme programming

all phases of the SDLC converge into a series of activities base don the basic processes of coding, testing, listening, and designing

inheritance

allows the creation of new classes that share some of the characteristics of existing classes ex: using a class of "person" to define another class of "customer"

techniques

are particular processes that analysts follow to help ensure their work is well thought out, complete, and comprehensible to others

tools

are typically computer programs that make it easy to use and benefit from techniques and to faithfully follow the guidelines of the overall development methodology

application software

computer software designed to support a specific organizational function or process

CASE Tools (acronym)

computer-aided software engineering tools

a methodology adopted by an organization will be

consistent with its general management style

In the 1950s

development focused on the processes the software performed

eXtreme programming

distinguished by its short cycles, incremental planning approach, focus on automated tests written by programmers and customers to monitor the dev process, and reliance on an evo approach to dev that lasts throughout the lifetime of the system

1990s

focused on systems integration; devs used visual programming environments, such as Power Builder and Visual Basic, to design the user interfaces for systems that run on client/server platforms

implementation can continue

for as long as the system exists b/c ongoing user support is also part of implementation

main purpose of CASE tools

helping programmers and analysis do their jobs more efficiently and more effectively by automating routine tasks

primary task of OO analysis

identifying objects and defining their structure and behavior and their relationships

What did 4th gen languages do that prior gen languages did not?

instructed a computer on what to do instead of how to do it

information systems analysis and design

is a complex, challenging, and stimulating organizational process that a team of business and systems professionals uses to develop and maintain computer-based information systems.

the goal of OOAD

is to make systems elements more reusable, thus improving system quality and the productivity of systems analysis and design

object class

logical grouping of objects that have the same (or similar) attributes and behaviors ex: "person" "customer" "product"

primary task of OO design

modeling the details of the objects' behavior and communicating with other objects to that system requirements are met

The 1960s

saw important breakthroughs in technology that enabled the development of smaller, faster, less expensive computers (minicomputers) and the beginnings of the software industry

systems development methodology

standard process followed in an organization to conduct all the steps necessary to analyze, design, implement, and maintain information systems

In the 1970s

systems development began to be viewed more as a science than an art; become more like engineering

planning

the 1st phase of SDLC; someone identifies the need for a new or enhanced system

analysis

the 2nd phase of the SDLC; the analyst thoroughly studies the organization's current procedures and the information systems used to perform organizational tasks

design

the 3rd phase of the SDLC; analysts convert the description of the recommended alternative solution into logical and then physical system specifications

implementation

the 4th phase of the SDLC; the information system is coded, tested, installed, and supported in the organization

maintenance

the 5th/final phase of SDLC; programmers make the changes that users ask for and modify the system to reflect evolving business conditions

The first procedural, or 3rd gen, computer programming languages didn't become available until

the beginning of the 1960s

the smaller and less risky a project

the more that agile/adaptive methodologies will apply

the larger and riskier a project

the more that traditional methodologies will apply

systems analyst

the organizational role most responsible for the analysis and design of information systems

logical design

the part of the design process that is independent of any specific hardware or software platform

physical design

the process by which the logical specifications are transformed into technology-specific details

In any given SDLC phase,

the project can return to an earlier phase if necessary

Systems Development Life Cycle (SDLC)

the traditional methodology used to develop, maintain, and replace information systems

objects

usually correspond to the real things an information system deals with, such as customers, suppliers, contracts, and rental agreements

The 1980s

were marked by major breakthroughs in computing in organizations, as microcomputers became key