CSC1100 - Chapter11 - Programming Languages and Program Development

Discovering Computers 2008

Chapter 11 Chapter 11 Chapter 11 Chapter 11

Programming Programming Programming Programming

Languages and Languages and Languages and Languages and

Program DevelopmentProgram DevelopmentProgram DevelopmentProgram Development

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Chapter 10 ObjectivesChapter 10 ObjectivesChapter 10 ObjectivesChapter 10 Objectives

Describe various ways to develop Web pages including HTML, scripting languages, DHTML, XML, WML, and Web page

authoring software

Describe various ways to develop Web pages including HTML, scripting languages, DHTML, XML, WML, and Web page

authoring softwareDifferentiate between machine and assembly languages

Differentiate between machine and assembly languages

Identify and discuss the purpose of procedural programming languagesIdentify and discuss the purpose of procedural programming languages

Identify the uses of popular multimedia authoring programs

Identify the uses of popular multimedia authoring programs

Identify and discuss the characteristics of object-oriented programming languages and

program development tools

Identify and discuss the characteristics of object-oriented programming languages and

program development tools

Identify the uses of other programming languages and other program development

tools

Identify the uses of other programming languages and other program development

tools

List the six steps in the program development cycle

List the six steps in the program development cycle

Differentiate between structured design and object-oriented design

Differentiate between structured design and object-oriented design

Explain the basic control structures and design tools used in designing solutions to

programming problems

Explain the basic control structures and design tools used in designing solutions to

programming problems

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Computer Programs and Programming LanguagesComputer Programs and Programming LanguagesComputer Programs and Programming LanguagesComputer Programs and Programming Languages

What is a computer program?� Series of instructions that directs computer to

perform tasks� Programming language— used to communicate

instructions

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Computer Programs and Programming LanguagesComputer Programs and Programming LanguagesComputer Programs and Programming LanguagesComputer Programs and Programming Languages

What are low-level languages and high-level languages?

High-level language

High-level language

Low-levellanguageLow-levellanguage

Machine-dependentMachine-dependent Often machine-Often machine-Machine-dependentruns only on one type of

computer

Machine-dependentruns only on one type of

computer

Often machine-independent

can run on many different types of computers and

operating systems

Often machine-independent

can run on many different types of computers and

operating systemsMachine and assembly languagesare low-levelMachine and assembly languagesare low-level

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LowLowLowLow----Level LanguagesLevel LanguagesLevel LanguagesLevel Languages

What is machine language?� Only language computer

directly recognizes� Uses a series of binary

digits (1s and 0s)with a combination of numbers combination of numbers and lettersthat represent binary digits

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LowLowLowLow----Level LanguagesLevel LanguagesLevel LanguagesLevel Languages

What is assembly language?� Instructions made up of

symbolic instruction codes, meaningful abbreviations and codes

� Source programcontains � Source programcontains code to be converted to machine language

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Procedural LanguagesProcedural LanguagesProcedural LanguagesProcedural Languages

What is a procedural language?

Uses series of English-like words to write instructions

Programmer writes instructions that tell computer what to

accomplish and how to do it

Often called thirdthird--generation language generation language

(3GL)(3GL)

accomplish and how to do it

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What is a compiler?� Program that

converts entire source program into machine machine languagebefore executing it

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What is an interpreter ?� Program that

translates and executesone program statement (code) at (code) at a time

� Does not produce object program

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What is COBOL?� Designed for business applications� English-like statements make code easy to read, write,

and maintain� COmmon Business-Oriented Language

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What is C?� Powerful language originally designed to write system

software� Requires professional programming skills

COBOL

C

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ObjectObjectObjectObject----Oriented Programming LanguagesOriented Programming LanguagesOriented Programming LanguagesOriented Programming Languages

What is an object-oriented programming (OOP) language?

Used to implement

object-oriented design

Major benefit is ability to

reuse existing objects

Event-driven—checks for

and responds to set of events

Java, C++, C#, and Visual Basic

are complete object-oriented

languageslanguagesObject is item that contains data and

proceduresthat act on data

Event is action to which program responds

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What is Java?� Developed by Sun

Microsystems� Similar to C++ but

uses just-in-time (JIT) compiler to (JIT) compiler to convert source code into machine code

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What is C++?� Includes all elements of C, plus additional features

for working with object-oriented concepts� Used to develop

database and Web applicationsWeb applications

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What is C#?� Object-oriented programming language based on C++� Accepted as a standard for Web applications and

XML-based Web services� Uses a JIT compiler� Resulting code is called Microsoft Intermediate � Resulting code is called Microsoft Intermediate

Language (MSIL)

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What is a visual programming language?

Visual programming environment (VPE)allows developers to

drag and drop objects to build programs

Provides Provides visual or visual or graphical interfacegraphical interface for for creating source codecreating source code

Programmer writes and implements program in segments

to build programs

Often used in Often used in RAD RAD (rapid application (rapid application

development)development)environmentenvironment

Sometimes calledSometimes calledfifthfifth--generation generation

languagelanguage

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What is VisualStudio?� .NET is set of technologies that allows program to run on Internet� Comprised ofVisual Basic, Visual C++, Visual C#, and Visual J#

Step 1. The developer designs the user interface.

Step 2. The developer assigns properties to each object on the form.

user interface.

Step 3. The developerwrites code to define the action of each command button.

Step 4. The developer tests the program.

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What is Delphi?� Powerful visual programming tool� Ideal for large-scale enterprise and Web applications

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What is PowerBuilder?� Another powerful visual programming tool� Best suited for Web-based and large-scale

enterprise object-oriented applications

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Other Programming LanguagesOther Programming LanguagesOther Programming LanguagesOther Programming Languages

� What are nonprocedural languagesand program development tools?

Nonprocedural Language

The programmer writes English-

Nonprocedural Language

The programmer writes English-

Program Development Tools

User-friendly programs

Program Development Tools

User-friendly programs The programmer writes English-like instructions or interacts with a visual environment to retrieve

data from files or a database

The programmer writes English-like instructions or interacts with a visual environment to retrieve

data from files or a database

User-friendly programs designed to assist both

programmers and users in creating programs

User-friendly programs designed to assist both

programmers and users in creating programs

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What is a fourth-generation language (4GL)?� Nonprocedural language that allows access to data in

database� Popular 4GL is SQL, query language that allows users to

manage data in relational DBMS

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Other Program Development ToolsOther Program Development ToolsOther Program Development ToolsOther Program Development Tools

What is an application generator?� Program that creates

source code or machine code from specification

� Consists of report writer, form, and menu generator� Form provides areas for

entering data

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Web Page DevelopmentWeb Page DevelopmentWeb Page DevelopmentWeb Page Development

What is HTML (Hypertext Markup Language)?� Used to create Web pages

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What is the common gateway interface (CGI)?� Communications standard

that defines how Web server communicates with outside sources� CGI script —program that

manages sending and receiving manages sending and receiving across CGI

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What is dynamic HTML (DHTML) ?� Allows developers to

include more graphical interest and interactivity in Web page

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What are XHTML , XML , and WML ?

XHTML XHTML (Extensible HTML)

enables Web sites to be displayed more easily on microbrowsers

XML XML

Includes features of HTML and XML

XML XML (Extensible Markup Language)

allows developers to create customized tags

WMLWML(Wireless Markup Language)

allows developers to design pages specifically for microbrowsers

Many PDAs and smart phones use WML as their

markup language

Server sends entire record to client, enabling client to do much of processing without

going back to serverRSS 2.0

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What is Web page authoring software?� Creates sophisticated Web pages without using HTML� Generates HTML

FlashFlashExpressionExpressionWebWeb

DreamweaverDreamweaver

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Multimedia Program DevelopmentMultimedia Program DevelopmentMultimedia Program DevelopmentMultimedia Program Development

What is multimedia authoring software?� Combines text,

graphics, animation, audio, and video into interactive presentation

� Used for computer-Used for computer-based training (CBT) and Web-based training (WBT)

� Software includes Toolbook, Authorware, and Director

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The Program Development CycleThe Program Development CycleThe Program Development CycleThe Program Development Cycle

What is the program development cycle?� Steps programmers use to build computer programs

� Programming team—Groupof programmers working on programprogram

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Step 1 Step 1 Step 1 Step 1 ———— Analyze RequirementsAnalyze RequirementsAnalyze RequirementsAnalyze Requirements

What is involved in analyzing the requirements?1. Review requirements2. Meet with systems analyst and users3. Identify input, output, processing, and data

components� IPO chart—� IPO chart—

Identifies program’s inputs, outputs, and processing steps

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Step 2 Step 2 Step 2 Step 2 ———— Design SolutionDesign SolutionDesign SolutionDesign Solution

What is involved in designing the solution?

ObjectObject--oriented oriented designdesignTwo Two

approachesapproaches

Programmer Programmer begins with general begins with general

design and moves toward design and moves toward detailed designdetailed design

Structured Structured designdesign, sometimes , sometimes

called topcalled top--down designdown design

Devise Devise solution solution algorithm, algorithm, stepstep--byby--step step procedure to procedure to solve problemsolve problem

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What is a hierarchy chart?� Shows program modules graphically� Also called structure chart

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What is object-oriented (OO) design?� Programmer packages data and

procedure into single unit, an object� Objects are grouped into classes

� Class diagramrepresents hierarchical relationships of classes graphicallyrelationships of classes graphically

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What is a sequence control structure?� Control structure that shows actions following each

other in order� Control structure depicts

logical order of program instructionsinstructions

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What is a selection control structure?� Tells program which

action to take, based on a certain condition

� Two types� Two types� Case control structure

� If-then-else control structure—yields one of two possibilities: true or false

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What is a case control structure?� Yields one of three or more possibilities

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What is a repetition control structure?� Enables program to perform one or more actions

repeatedly� Do-while control

structure—repeats as long as condition is truetrue

� Do-until control structure—repeats until condition is true

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What is a program flowchart?� Graphically shows logic

in solution algorithm

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What is an example of a flowchart?

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What is flowcharting software?� Used by programmers to develop flowcharts

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What is pseudocode?� Uses condensed form

of English to convey program logic

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Step 3 Step 3 Step 3 Step 3 ———— Validate DesignValidate DesignValidate DesignValidate Design

What is involved in validating the design?

Check program design for accuracy

Logic errorLogic error

Programmer checks logic for correctness

and attempts to uncover logic errors

Logic errorLogic errordesign flaw that causes

inaccurate results

Test dataTest datasample data that

mimics real data that program will process

Desk checkDesk checkprogrammers use test

data to step through logic

Inspectionsystems analyst reviews

deliverables during the system development cycle

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Step 4 Step 4 Step 4 Step 4 ———— Implement DesignImplement DesignImplement DesignImplement Design

What is implementation?� Writing the code that translates the design into a program

� Syntax—rules that specify how to write instructions

� Comments—program documentation� Extreme programming (XP)—coding and testing as soon as

requirements are defined

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Step 5 Step 5 Step 5 Step 5 ———— Test SolutionTest SolutionTest SolutionTest Solution

What is involved in testing the solution?

Ensure program runs correctly Ensure program runs correctly and is error freeand is error free

DebuggingDebugging——locating and locating and correcting syntax and logic correcting syntax and logic

errors, orerrors, or bugsbugserrors, orerrors, or bugsbugs

Test copy of program, Test copy of program, called called betabeta, sometimes , sometimes

used to find bugsused to find bugs

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Step 6 Step 6 Step 6 Step 6 ———— Document SolutionDocument SolutionDocument SolutionDocument Solution

What is involved in documenting the solution?� Programmer performs two activities

Reviewsprogram code — removes dead code, Reviewsprogram code — removes dead code, — removes dead code, program instructions that program never

executes

— removes dead code, program instructions that program never

executesReviews

documentationReviews

documentation

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Summary of Programming Languages and Program DevelopmentSummary of Programming Languages and Program DevelopmentSummary of Programming Languages and Program DevelopmentSummary of Programming Languages and Program Development

Various programming languages used to write and develop

computer programs

Various programming languages used to write and develop

computer programsWeb development and multimedia

development toolsWeb development and multimedia

development toolsThe program development

cycle and the tools used to make this process efficient

The program development cycle and the tools used to make

this process efficient

development toolsdevelopment tools

Chapter 10 Complete

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ADDITIONSADDITIONSADDITIONSADDITIONS

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What is RPG (Report Program Generator)?� Nonprocedural language used for generating reports,

performing computations, and updating files

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What are other available programming languages?

ALGOLALGOLALGOLALGOLADAADAADAADA APLAPLAPLAPL

BASICBASICBASICBASIC HYPERTALKHYPERTALKHYPERTALKHYPERTALKFORTRANFORTRANFORTRANFORTRANFORTHFORTHFORTHFORTHBASICBASICBASICBASIC HYPERTALKHYPERTALKHYPERTALKHYPERTALKFORTRANFORTRANFORTRANFORTRANFORTHFORTHFORTHFORTH

LISPLISPLISPLISP MODULAMODULA--22MODULAMODULA--22LOGOLOGOLOGOLOGO

PASCALPASCALPASCALPASCAL PROLOGPROLOGPROLOGPROLOGPL/1PL/1PL/1PL/1PILOTPILOTPILOTPILOT

SMALLTALKSMALLTALKSMALLTALKSMALLTALK

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Other Program Development ToolsOther Program Development ToolsOther Program Development ToolsOther Program Development Tools

What is a macro?� Series of statements that instructs an application how

to complete a task

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How are special effects and interactive elementsadded to a Web page?

ScriptScriptinterpreted

program that

AppletAppletusually runs on client, but

ServletServletapplet that

runs on

ActiveX ActiveX controlcontrol

small program

CounterCountertracks

number of visitors to Web site

Image mapImage mapgraphic

image that points to

URL

program that runs on client

on client, but is compiled

Processing Processing formform

collects data from visitors to Web site

runs on server

small program that runs on

client

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What is a scripting language?� Typically easy to learn and use

� JavaScript� Perl (Practical Extraction

and Report Language)

� PHP (PHP: Hypertext Preprocessor)Preprocessor)

� Rexx (Restructured eXtended eXecutor)

� TCL (Tool Command Language)

� VBScript (Visual Basic, Scripting Edition)

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What is Ajax?� Stands for Asynchronous JavaScript and XML� Method of creating interactive Web applications designed

to provide immediate response� Combines JavaScript, HTML or XHTML, and XML� Google Maps and Flickr use Ajax� Google Maps and Flickr use Ajax

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What is Ruby on Rails(RoR)?� Also called Rails� Open source framework that provides technologies for

developing object-oriented, database-driven Web sites� Ruby is derived from a variety of languages, including Ada,

LISP, Perl, and SmalltalkLISP, Perl, and Smalltalk

Technology

CSC1100 - Chapter11 - Programming Languages and Program Development