chapter 15 program development and programming languages

Chapter 15Program Development and Programming Languages

Explain the six steps in the program development life cycle

Describe top-down program design

Explain structured program design and the three basic

control structures

Explain the differences among the categories of programming

languages

Describe the object-oriented approach to program

development

Identify programming languages commonly used

today

Identify the uses of application generators, macros, and RAD

tools

Describe various Web page development tools, including

HTML, DHTML, XML, and WML

Identify uses of multimedia authoring packages

Chapter 15 Objectives

Next

p.15.2

programming language

A set of words, symbols, and codes that enables a

programmer to communicate instructions

to a computer

What is a Computer Program?

What is a computer program? A set of instructions that

directs a computer to perform tasks

Computer programmers

• use program development tools that generate these instructions automatically

• use a programming language to write these instructions themselvesp.15.2

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The Program Development Life CycleWhat is the

program development life cycle (PDLC)?

A set of steps programmers use to build computer programs

p.15.22 Fig. 15-1

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The Program Development Life CycleHow is program development related to system

development?

Program development is an ongoing process within system development

p.15.3 Fig. 15-2

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The Program Development Life CycleWhat initiates the PDLC?

During the analysis phase of the system development life cycle (SDLC), the development team recommends how to handle software needs

If the company recommends in-house development, programmers begin the PDLC as part of the implementation phase

p.15.3 Fig. 15-2

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The Program Development Life CycleWhat is the program specification package?

A detailed set of requirements for a system created by the systems analyst during the design phase of the SDLC

Identifies the input, output, processing, and data requirements of each program and the relationships among programs

The scope of the program specification package largely determines how many programmers work on the program developmentp.15.3

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programming team

A group of programmers who

develop the programs

Click to view video

Step 1 – Analyze Problem

What is involved in analyzing the problem? Analyze the problem

the program(s) should solve so you can begin to develop an appropriate solution

In most cases, the solution requires more than one program

Three major tasks

p.15.4

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Review the program specifications

package

Meet with the systems analyst and

users

Identify each program’s input, output, and

processing components


Package contains a variety of deliverables that identify input, output, design and data requirements

By thoroughly reviewing the package, the programmer understands the nature and requirements of each programp.15. 4

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charts

diagrams

reports

screen and report layout charts

systems flowcharts

structured English

decision tables and decision trees

data dictionary

Why does the programmer review the program specification package?


What is an IPO chart? Also called a defining diagram Identifies a program’s inputs, its outputs, and the

processing steps required to transform the inputs into the outputs

p.15.4 Fig. 15-3

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structured design

Tasks 2 and 3

Determines how to build the programs based on the

requirements

Step 2 – Design Programs

Three tasks

• grouping each program’s activities into modules

• devising a solution algorithm for each module

• testing the solution algorithms

p.15.5

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top-down design

Task 1

Focuses on what the program should do

What is involved in designing programs?


Breaks down the original set of program specifications into smaller, more manageable sections

p.15.5

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Click to view Web Linkthen click Top-Down Design

Identify the the major functions of a program, called the main routine or

the main module

Decompose (break down) the main routine into smaller sections called subroutines

Analyze each subroutine to determine if it can be decomposed further

Continue decomposing subroutines until each one performs a single function

A section of a program that performs a single function is a module

What is top-down design?

http://scsite.com/dc2002/ch15/weblink.htm


What is a hierarchy chart? Also called a structure chart or top-down chart Used to show program modules graphically

p.15. 6Fig. 15-4

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What is structured design? A technique that builds all

program logic from a combination of three basic control structures

A control structure is a design that determines the logical order of program instructions

• also called a construct Each module typically

contains more than one control structure

p.15.6

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Click to view Web Linkthen click Structured Design

sequence control

structure

selection control

structure

repetition control

structure



What is a sequence control structure? Shows one or

more actions following each other in order

Actions

• inputs

• processes

• outputs

p.15.7 Fig. 15-5

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What is a selection control structure? Tells the

program which action to take, based on a certain condition

Two common types of selection control structures

p.15.7

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if-then-else control structure

case control structure


What is an if-then-else control structure? Allows a program to evaluate the condition and yields

one of two possibilities: true or false If the result of the condition is true, the program

performs one action

If the result is false, the program performs a different (or possibly no) action

p.15.7 Fig. 15-6

Next


What is a case control structure? A condition can yield one of three or more

possibilities

p.15.7 Fig. 15-7

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What is a repetition control structure? Also called the

iteration control structure or a loop

Used when a program performs one or more actions repeatedly as long as a certain condition is met

Two forms

p.15.8

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do-while control

structure

do-until control

structure


What is a do-while control structure? Repeats one or more

times as long as a condition is true• Tests a condition at the

beginning of the loop• If the result is true, the

program executes the action(s) inside the loop

• Program loops back and tests the condition again

• Looping continues until the condition becomes false

p.15.8 Fig. 15-8

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What is a do-until control structure? Tests the condition

at the the end of the loop

The action(s) will always execute at least once

Continues looping until the condition is true, and then stops

p.15.8 Fig. 15-9

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The program, each of its modules, and each of its control structures must have• No dead code• No infinite

loops• One entry

point• One exit point

p.15.8

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dead code

Any code, or program instruction, that a program never executes

infinite loop

A set of instructions that repeats continuously

entry point

The location where a program, a module, or a control structure begins

exit point

The location where it ends

What are the guidelines of a proper program?


How are entry and exit points shown?

Program modules often have control structures nested inside one another

Each control structure should have one entry point and one exit point

p.15.9 Fig. 15-10

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What is a solution algorithm? Also called program

logic A graphical or written

description of the step-by-step procedures in a module

To help develop a solution algorithm, programmers use design tools

p.15.9

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program flowchart

Nassi-Schneiderman

charts

pseudocode


What is a program flowchart? Graphically shows

the logic in a solution algorithm

Follows a set of standards published by the American National Standards Institute (ANSI) in the early 1960s

p.15.9 Fig. 15-11

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How is a program flowchart drawn? Most

symbols connect with solid lines showing the direction of the program

Dotted lines connect comment symbols

Next

comment symbol or annotation symbol

Explains or clarifies logicp.15.10 Fig. 15-12


What is flowcharting software? Used to

develop flowcharts

Makes it easy to modify and update flowcharts

p.15.10 Fig. 15-13

Next

Click to view Web Linkthen click Flowcharting Software



What is a Nassi-Schneiderman (N-S) chart? Graphically shows the logic in a solution algorithm Sometimes called structured flowcharts

p.15.11 Fig. 15-14

Next


What is pseudocode? Uses a condensed

form of English to convey program logic

Also uses indentation to identify the three basic control structures

p.15.12 Fig. 15-15

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What is a quality review? The programmer

checks the logic for correctness and attempts to uncover logic errors

Two techniques for reviewing a solution algorithm• desk check• structured

walkthrough

p.1512

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logic error

A flaw in the design that causes

inaccurate results

5. Repeating Steps 3 and 4 for each set of test data

4. Comparing the expected result from Step 2 to the actual result from Step 3

3. Stepping through the solution algorithm using one set of test data and writing down the actual result obtained (output) using the solution algorithm


The use of test data to step though a program’s logic

Test data is sample data that mimics data the program might process once it is in production

Involves five steps

p.15.12

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2. Determining the expected result (output) for each set of data, without using the solution algorithm

1. Developing sets of test data (inputs)

What is a desk check?

Detecting errors and making

improvements early in the PDLC

reduces the overall time and cost of

program development


What is a structured walkthrough? A more formal technique

for checking the solution algorithm

The programmer explains the logic of the algorithm while members of the programming team step through the program logic

Purpose is to identify errors in the program logic and check for possible improvements in program design

p.15.12

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Step 3 – Code Programs

What is involved in coding programs? Two steps

• translating the solution algorithm into a programming language

• entering the programming language code into the computer

Each of the many programming languages has a particular syntax

p.15.13

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syntax

The set of grammar and rules that

specifies how to write instructions for a solution algorithm

Step 3 – Code Programs

How are programs documented? A programmer should take time to document the program code

thoroughly Comments or remarks are included in a program as documentation Global comments explain the program’s purpose and identify the

program name, its author, and the date written Internal comments explain the purpose of the code statements

within the program

p.15.13 Fig. 15-16

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global comments

global comments

internal commentsinternal

comments

syntax errors

Occur when the code violates the syntax, or grammar, of the programming

language

Usually discovered the first time a program code is executed on the

computer

Step 4 – Test Programs

What is involved in testing programs? Goal is to ensure

the program runs correctly and is error free

Two typical types of errors

• syntax errors

• logic errors

p.15.13

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logic errors

Flaw in the design that generates inaccurate results

Systems analyst develops test data including both valid and invalid input

data


What is a run time error? A program failure

occurring while a program is being executed

Programmers use test data to deliberately cause a run time error in order to test the program

p.15.13

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What is debugging? The process of

locating and correcting the syntax and logic errors in a program

Errors themselves are the bugs

The first bug was said to be a moth lodged in a computer's electronic components

p.15.14 Fig. 15-17

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What is a debug utility? Also called a

debugger Allows you to

identify syntax errors and to find logic errors

You can examine program values while the program runs in slow motion

p.15.14

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millennium bug

Also called the Y2K bug

Took effect when the computer date rolled

over to January 1, 2000

Non Y2K compliant computers read the

date as 01/01/00

Step 5 – Formalize Solution

What is involved in formalizing a solution? The programmer performs two

activities• review the program code

– look for any dead code and remove it

– run the program one final time to verify it still works

• review all the documentation – ensures all

documentation is complete and accurate

– includes a number of types of documentation

p.15.15

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hierarchy chart

solution algorithm in the form of a program

flowchart, and N-S chart, or pseudocode

test data

program code listings that contain global and

internal comments

Step 6 – Maintain Programs

What is involved in maintaining programs? Two activities

• correcting errors• adding enhancements

– involves modifying existing programs to improve their functionality

When a program is implemented, or placed into production, users interact with the programs• programs process actual, or

live, transactions• users identify errors and

enhancements

p.15.15

Next

When users identify errors or enhancements, they typically

notify the systems analyst

The systems analyst contacts and meets with a

programmer

They begin to analyze the problem or enhancement,

which is Step 1 of the PDLC

Programming Languages and Program Development ToolsWhat are programming languages and program

development tools?

p.15.16

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programming language

A set of words, symbols, and codes that enables a

programmer to communicate a solution

algorithm to the computer

program development tool

Consists of user-friendly software products

designed to assist both programmers and

nontechnical users with the creation of information

system solutions

machine languages

Categories of Programming LanguagesWhat are the categories of programming

languages?

p.15.16

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Click to view video

Click to viewanimation

assembly languages

third-generation languages

fourth-generation languages

fifth-generation languages

Five major categories of programming languages

machine and assembly languages are low-level

Categories of Programming LanguagesWhat are low- and high-level programming

languages?

p.15.16

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machine-dependent language

Only runs on one particular computer

low-level language

A programming language that is machine dependent

third-generation, fourth-generation, and fifth-generation

languages are high-level

machine-independent language

Can run on many different types of computers and

operating systems

high-level language

A language that is machine independent

Languages are classified as either low level or high level

Categories of Programming LanguagesWhat is machine

language? The first generation of

programming languages The only language the

computer directly understands

Uses a series of binary digits (1s and 0s) or a combination of numbers and letters that represent binary digits

Binary digits correspond to the on and off electrical states of a computer

p.15.16 Fig. 15-18

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Categories of Programming LanguagesWhat is assembly

language? The second generation of

programming languages A programmer writes

instructions using symbolic instruction codes

Next

symbolic instruction codes

Also called mnemonics

Meaningful abbreviations and codesp.15.16 Fig. 15-19

macro

Generates multiple machine language instructions for a single assembly language

instruction

Saves the programmer time during program development

Categories of Programming Languages

p.15.17

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symbolic address

A meaningful name that identifies a storage location

Assembler

Converts the assembly language source program into machine language so

that the computer can understand it

Source program

The program that contains the assembly language code

What are features of assembly languages?

Categories of Programming LanguagesWhat is a third generation language (3GL)?

Uses a series of English-like words to write instructions A procedural language

• requires the program instructions tell the computer what to accomplish and how to do it

p.15.18 Fig. 15-20

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source program

The 3GL code

Categories of Programming LanguagesWhat is a compiler?

Converts the entire source program into machine language before executing it

The compiler checks the source program’s syntax

Makes sure the program properly defines the data it will use in calculations or comparisons

Produces a program listing which contains the source code and a list of any syntax errors

Translates an entire program before executing it

p.15.18 Fig. 15-20

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object code

Also called an object program

The machine language version that results from compiling the 3GL

Categories of Programming LanguagesWhat is an interpreter?

Reads a code statement Converts it to one or more machine language

instructions Executes those machine language instructions Translates and executes one program code statement at

a time Does not

produce an object program

p.15.18 Fig. 15-21

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Categories of Programming LanguagesWhat is a fourth-generation language (4GL)?

Uses English-like statements

The syntax is closer to human language than that of a 3GL

A nonprocedural language• programmer only

specifies what the program should accomplish without explaining how

• many 4GLs work with a database and its project dictionaryp.15.19 Fig. 15-22

Next

Categories of Programming Languages

p.15.19

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SQL

A query language enabling users and

programmers to retrieve data from database tables

report writer

Also called a report generator

Software that allows you to design a report on the screen, retrieve data into

the report design, and then display or print the

report

Builds a 4GL query that enables you to access

the data

What are some examples of 4GLs?

Categories of Programming LanguagesWhat is a fifth-generation language (5GL)?

p.15.20 Fig. 15-25

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One that provides a visual or graphical interface for creating the source code

Often converts the source code to machine language using a 3GL or 4GL compiler

Object-oriented and Web development tools sometimes use a 5GL such as Visual Basic

Object-Oriented Program DevelopmentWhat is the object-oriented (OO) approach?

The programmer can package the data and the program (or procedure) into a single unit, called an object

When the structure of an object changes, any program that accesses the object automatically accesses the change

p.15.20

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object

An item that can contain both data and the procedures that read or manipulate that data

method or operation

The procedure in the object that contains activities that read or manipulate the data

attributes or variables

The data elements

encapsulation or information hiding

The concept of packaging methods and attributes into a single object

Object-Oriented Program DevelopmentWhat is a class?

A larger category of objects Each object in a class shares methods and attributes

that are part of the original object A generalization

hierarchy shows relationships between classes of an object

p.15.20 Fig. 15-23

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Object-Oriented Program DevelopmentWhat are some terms related to classes?

Each class can have one or more subclasses The higher-level class is called a superclass Inheritance is the concept of lower levels inheriting

methods and attributes of higher levels

An object instance is a specific occurrence of an object or object class

A message tells an object what to dop.15.20 Fig. 15-23

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Object-Oriented Program DevelopmentWhat is the Object Management Group (OMG)?

An international organization that establishes guidelines and specifications for OO application development

Has adopted UML and CORBA as standards

p.15.21

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UML (Unified Modeling Language)

Contains the standard notation for analysis,

design, and documentation for the OO approach

CORBA (Common Object Request Broker Architecture)

Defines how objects in separate programs on a

network can communicate with each other

Object-Oriented Program DevelopmentWhat is object-oriented programming

(OOP) language? A language that uses the

OO approach An OOP is event driven

• checks for and responds to a set of events

C++ is a complete object-oriented language

p.15.21

Next

Click to view Web Linkthen click Object-Oriented Programming Languages

event

The OOP term for message


Programming Languages

What are the most widely used programming languages?

Hundreds of programming languages exist

A few are used widely enough to be recognized as standards

Most are high-level languages

p.15.22

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BASIC

Visual Basic

COBOL

C

C++

RPG


How can you compute gross pay? Figures on the

following slides show program code in several programming languages

The code solves a simple payroll problem – computing the gross pay for an employee

p.15.22

Next

1. Multiply the regular time hours worked by the hourly rate of pay to obtain the regular time pay

Regular pay = regular hours x hourly rate of pay

2. Multiply the overtime hours by 1.5 times the hourly rate of pay to obtain the overtime pay

Overtime pay = overtime hours x 1.5 x hourly rate of pay

3. Add the regular time pay and the overtime pay together

Gross pay = regular time pay + overtime pay


What is BASIC? Beginner's All-purpose Symbolic Instruction Code Developed by John Kemeny and Thomas Kurtz in the mid-

1960s at Dartmouth College Designed for use as a simple, interactive problem-solving

language

p.15.22 Fig. 15-24

Next


What is Visual Basic? A Windows-based application that assists programmers

in developing other event-driven Windows-based applications

Developed by Microsoft Corporation in the early 1990s

p.15.22 Fig. 15-25

Next

Click to view Web Linkthen click Visual Basic


Step 1: Programmer designs user interface. Regular Time Hours Worked, Overtime Hours Worked, and Hourly Pay Rate are text boxes, in which the user enters data. COMPUTE and CLEAR are command buttons. All other objects are labels.

Step 2: Programmer assigns properties to each object on the form. Objects include text boxes, command buttons, labels, and the form itself.

Step 3: Programmer writes code and assigns it to the COMPUTE button.


How is a Visual Basic application created?

p.15.23 Fig. 15-25

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Step 4: Programmer tests the application. Gross pay displays after COMPUTE button is clicked.


What is COBOL? COmmon Business-Oriented Language Developed out of a joint effort between the United States

government, businesses, and major universities in the early 1960s Naval officer Grace Hopper was a prime developer of the COBOL

language One of the

more widely used procedural programming languages for business applications

p.15.24 Fig. 15-26

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Technology Trailblazer

Grace Hopper Programmed the Mark I

‘computer engine’ to find the angles to aim naval guns in varying weather conditions

Helped build and program several other early computers

Credited with finding the first computer ‘bug’

Developed the first compiler Created the FLOW-MATIC

programming language that laid the foundation for COBOLp.15.24

Next

Click to view Web Linkthen click Grace Hopper

http://scsite.com/dc2002/people.htm


What is C? Developed in the early 1970s by Dennis Ritchie at Bell

Laboratories Originally designed for writing system software A powerful language that requires professional programming

skills

p.15.25 Fig. 15-27

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Technology Trailblazer

Dennis Ritchie Developed C at Bell

Labs in the early 1970s

Tweaked an earlier programming language, B, to make it portable

C became extremely popular outside of Bell Labs after 1980

Awarded the National Medal of Technology in 1999

p.15.25

Next

Click to view Web Linkthen click Dennis Ritchie

http://scsite.com/dc2002/people.htm


What is C++? Developed in the 1980s by Bjarne

Sroustrup at Bell Laboratories An object-oriented programming

language An extension of the C programming

language Includes all the elements of the C

language plus has additional features for working with objects, classes, events, and other object-oriented concepts

p.15.25

Next

Click to view Web Linkthen click C++

C#

A newer programming language that

combines features of C and C++

Best suited for development of

Web applications



What is RPG? Report Program Generator Introduced by IBM in the early 1960s to assist

businesses in generating reports

Businesses also use RPG for complex computations and file updating

A nonprocedural language

p.15.26 Fig. 15-28

Next


What are some other programming languages?

p.15.26 Fig. 15-29

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RAD tools: Visual Basic, Delphi, and PowerBuilder

Program Development Tools

What are program development tools? User-friendly software

products designed to help both program developers and nontechnical users create solutions to information requirements

Empower nontechnical users by giving them the ability to write simple programs on their own

Allows programmers and IT professionals to focus development efforts on larger projects

p.15.27

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macros

application generators


What is an application generator?

Sometimes called a program generator A program that allows you to build an

application without writing the extensive code required by a 3GL

Developer works with menu-driven tools that have graphical user interfaces

Typically includes a report writer, form, and menu generatorp.15.27

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menu generator

Allows the developer to create a menu, or

list of choices, for the application options


What are report writers and forms? A report writer allows

you to design a report on the screen, retrieve data into the report design, and then display or print the report

A form is a window on the screen that provides areas for entering or changing data in a database

p.15.27 Fig. 15-30

Next


What is a macro? A series of statements that

instructs an application how to complete a task

Can automate routine, repetitive, or difficult tasks in an application such as word processing, spreadsheet, or database programs

You usually create a macro in one of two ways

• record the macro

• write the macrop.15.28

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macro recorder

Used to automate a routine or

repetitive task

Records all actions until

turned off

VBA macro used to automate an

auto loan computation

VBA macro used to automate an

auto loan computation


What is Visual Basic for Applications (VBA)? Used to write your

own macros Macros use the

three basic structured programming constructs (sequence, selection, and iteration) within modules

Also use objects, classes, and other object-oriented concepts

p.15.28 Fig. 15-31

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Macro dialog

box

Macro dialog

box

Loan Data button

Loan Data button

Macro dialog box in Excel window guiding the user through the data

entry process

Macro dialog box in Excel window guiding the user through the data

entry process


What is rapid application development (RAD)? The concept of developing

software throughout the system development process

A common technique is prototyping• a prototype is a working

model of the proposed system

RAD tools are used to develop easy-to-maintain, component-based applications• component is another term

for object• three popular RAD toolsp.15.29

Next

Click to view Web Linkthen click Rapid Application Development

Visual Basic

Delphi

PowerBuilder



What are Visual Basic and Delphi? Visual basic

• A Windows-based application that assists programmers in developing other event-driven Windows-based applications

• One of the first programming environments to provide a visual programming environment (VPE)

Delphi• Offers a drag-and-drop VPE• Provides full object-oriented

capabilities

p.15.29

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visual programming environment (VPE)

Allows developers to drag-and-drop objects

to build programs


What is PowerBuilder? Uses a

proprietary object-oriented language for its application development

Language is called PowerScript

Can create powerful applications

p.15.30 Fig. 15-32

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Company on the Cutting Edge

p.15.30

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Click to view Web Linkthen click Sybase

Developer of PowerBuilder Enterprise, Powersoft, PowerStudio, and Adaptive Component Architecture

Selected as the company with Best Customer Support in the computer industry by InfoWorld readers

Products help developers efficiently create Internet applications and client/server programs

http://scsite.com/dc2002/companies.htm

Web Page Program Development

A Web page is a linked document that can contain text, graphics, video, and audio posted on the World Wide Web

Web page authors, the designers of Web pages, use a variety of techniques to develop Web pagesp.15.31

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HTML

Scripts, Applets, Servlets, and

ActiveX ControlsJava, JavaScript,

VBScript, and Perl

Dynamic HTML

XHTML, XML, and WML

Web page authoring software

What is involved in developing Web pages?

<B><B><HR><HR>

<P><P>


p.15.31

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tags or markups

Codes that specify links to other documents and

indicate how the Web page displays when viewed on the Web

Web page

A file that contains both text and HTML

tags

A special formatting language that programmers use to create Web pages

View Web pages written with HTML in a Web browser

Not actually a programming language• a language with specific

syntax rules for defining the placement and format of text, graphics, video, and audio on a Web page

What is hypertext markup language (HTML)?


How does HTML code look?

HTML code can be written using any

text editor or entered into any standard word

processing software package

Save the code as an ASCII file with an .htm or .html

extensionp.15.31 Fig. 15-33

Next


How does HTML relate to a Web page? Web page

created from part of the Web code shown in Figure 15-33

p.15.31 Fig. 15-34

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How are dynamic elements added to a Web page? Small programs

called scripts, applets, servlets, and ActiveX controls are used to add dynamic content and interactive elements• short

programs that run inside of another program

p.15.32

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scriptAn interpreted program that runs on

the client

appletAlso usually runs on the client,

but it is compiled

servletAn applet that runs on the server

ActiveX controlA small program that runs on your

computer, instead of the server

Uses ActiveX technology, a set of object-oriented technologies by Microsoft


What are some special effects that can be added with scripts, applets, servlets, and ActiveX controls? Add multimedia effects

• animated graphics• scrolling messages• calendars• advertisements

Include interactive capabilities• cookies• shopping carts• games• counters• image maps• processing forms

p.15.32

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counter

Tracks the number of visitors to a Web site

image map

A graphical image that points to a URL

When you click a certain part of the graphical image, your Web browser sends the coordinates of the clicked location to the Web server, which in turn locates the corresponding URL


What is a processing form?

Collects data from visitors to a Web site, who fill in blank fields and then click a button that sends the information

Activates with a script or applet

p.15.32 Fig. 15-35

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What is the common gateway interface (CGI)?

The communications standard that defines how a Web server communicates with outside sources

The program that manages the sending and receiving across the CGI is a CGI script, or CGI program

p.15.33

Next

Click to view Web Linkthen click CGI Programs

You can download CGI programs from the Web, purchase them, or write your

own


Web serverStep 2: Webmaster creates a link between CGI program and Web page. When a user displays the Web page, the CGI program automatically starts.

Step 3: When a user submits a request, it is sent to the CGI program. The CGI program contacts the database and requests information for the user. In this case, it looks for a movie titled Secret Garden.

Step 1: Programmer stores CGI program in a special folder on the Web server, such as /cgi-bin.

Step 4: The CGI program receives information from the database, assembles it in an HTML format, and sends it to the user’s Web browser.


How does a CGI program work?

p.15.33 Fig. 15-36

Next


What is a scripting language? An interpreted

language that typically is easy to learn and use

Often used to write CGI scripts

p.15.34

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Java

JavaScript

VBScript

Perl


What is Java? Developed by Sun

Microsystems A compiled object-oriented

programming language used to write stand-alone applications, as well as applets and servlets

Source code is compiled into bytecode, instead of object code, which is executed by a Java interpreter

p.15.34

Next

Click to view Web Linkthen click Java

JavaBeans or Beans

Code segments used to create a Java application

Platform independent


How does a sample of Java code look?

p.15.34 Fig. 15-37

Next

Click to view video

Java applet code

resulting screen



What is JavaScript? An interpreted language that

allows the programmer to add dynamic content and interactive elements to a Web page

JavaScript code is inserted directly into an HTML document

Much simpler than Java To run JavaScript, your browser

must support it• Netscape supports it• Internet Explorer supports a

subset called JScript

p.15.35

Next

The result of a joint venture between Sun

Microsystems and Netscape

Communications Corporation

open language

Anyone can use it without purchasing

a license


How does a sample of JavaScript code look?

p.15.35 Fig. 15-38

Next

Click to view Web Linkthen click javaScript

JavaScript code

Pop-up window

made with JavaScript

code



p.15.36

Next

VBScript (Visual Basic Scripting Edition)

A subset of the Visual Basic language

Allows you to add intelligence and interactivity to Web pages

You embed VBScript code directly into an HTML document

Perl (Practical Extraction and Report Language)

First developed by Larry Wall at NASA’s Jet Propulsion Laboratory

Originally a procedural language similar to C, but now is an interpreted scripting language

What are other scripting languages?


What is dynamic HTML (DHTML)? A newer

type of HTML

Allows you to include more graphical interest and interactivity

p.15.36 Fig. 15-39

Next

Click to view Web Linkthen click Dynamic HTML

When you point to the Recreational Vehicles

link, image to the right is a camper and text

discusses communication from

your RV

When you point to the Recreational Vehicles

link, image to the right is a camper and text

discusses communication from

your RV

When you point to the Rural Regions link,

image to the right is a farmer and text

discusses calling from the farm

When you point to the Rural Regions link,

image to the right is a farmer and text

discusses calling from the farm



What are features of DHTML? DHTML works by using the document object model,

style sheets, and scripting languages

p.15.37

Next

cascading style sheets (CSS)

Contain the formats for how a particular object should display in a Web

browser

document object model (DOM)

Defines every item on a Web page as an

object

Allows you to change properties, such as

color or size, of any or all of these objects on

the Web page


What are XHTML, XML, and WML?

p.15.37

Next

Click to view Web Linkthen click WML

XHTML (eXtensible HTML)

Includes features of HTML and XML

XML (eXtensible Markup Language)

Allows Web page developers to create customized tags, as

well as use predefined tags

Uses XSL (eXtensible Stylesheet

Language) as its style sheet

specification

WML (wireless markup language)

Allows Web page developers to design pages

specifically for microbrowsers

A subset of XML

Uses the wireless application

protocol (WAP)



What is Web page authoring software?

Sometimes called an HTML editor

Allows you to create sophisticated Web pages that include graphical images, video, audio, animation, and other special effects

Generates HTML tags from your Web page design

p.15.38

Next

Adobe GoLive

Lotus FastSite

Macromedia Dreamweaver

Macromedia Flash

Microsoft FrontPage

Multimedia Program Development

What is multimedia authoring software? Also called

authorware Allows you to

combine text, graphics, animation, audio, and video into an interactive presentation

p.15.38

Next

Toolbook

Authorware

Director


How is multimedia authoring software used? Computer-based

training (CBT) or computer-aided instruction (CAI)

CBT software is called courseware

Web-based training (WBT)

Distance learning, distance education, or online learning

p.15.38 Fig. 15-40

Next


What is ToolBook? From click2learn.com, Inc. Has a graphical user interface Uses an

object-oriented approach

Can convent multimedia applications into HTML and Java

p.15.40 Fig. 15-41

Next


What is Authorware?

p.15.40

Next

Software developed by Macromedia

Multimedia authoring software package

Provides the tools developers need to build interactive multimedia training and educational programs

Powerful authoring environment for development of interactive multimedia

magazines

catalogs

reference titles for CD-ROMs and DVD-ROMs

applications for kiosks


What is Director?

p.15.40 Fig. 15-40

Next

Also from Macromedia

A popular multimedia authoring program with powerful features

Allows you to create highly interactive multimedia applications

Includes Lingo, a built-in object-oriented scripting language

An application created using Director

Standards

Portability

Suitability

Interface

4. Portability to other systems

3. Suitability of the language to the application

2. Interface with other programs

Selecting a Programming Language or Program Development Tool

p.15.40

Next

1. Standards of the organization

What factors should be considered in selecting a programming language?

Company on the Cutting Edge

Macromedia

Software used by more than 1 million professional Web developers to author, produce, deliver, and analyze Web content

Dreamweaver is the leading platform in 70 percent of the market

Flash Player is the most widely Web-distributed software in history

Nearly 20 million users have registered their copies of Shockwave

p.15.41

Next

Click to view Web Linkthen click Macromedia

http://scsite.com/dc2002/companies.htm

Summary of Program Development and Programming Languages

What is a computer program? The program development life cycle Step 1 – Analyze problem Step 2 – Design programs Step 3 – Code programs Step 4 – Test programs Step 5 – Formalize solution Step 6 – Maintain programs Programming languages and program development tools

Summary of Program Development and Programming Languages (cont.)

Categories of programming languages Object-oriented program development Programming languages Program development tools Web page program development Multimedia program development Selecting a programming language or program development tool

Chapter 15 Complete

chapter 15 program development and programming languages

Documents

program developmentp

program specification

inhouse development

development team

design programswhat

design phase

set of instructions

set of steps programmers