MD240 Software for Designing and Developing New Software

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MD240Software for Designing and Developing New
Software
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Agenda

• Evolution of Programming
• History of the Programming Process
• Software Application Frameworks
• Object Oriented Programming
• Visual Programming
• Internet Programming

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Evolution of Programming
TREND Evolution from painful command-line
compilers, to simple integrated development
environments (IDEs), to multiple-desktop
integrated IDEs
TREND Evolution from costly programming tools to
freely available open source development tools.
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Evolution of Programming Languages

• Evolution of Programming Languages
• Machine language 0-1 long difficult
  programming
• Assembly language assemble repetitive
  instructions, shorter code
• Procedural language include commands, shorter
  code
• Non-procedural languages application
  generators commands specify results
• Intelligent languages natural language
  processing

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Building Computer ProgramsVarious Ways of
Running Programs

• Interactive
• user types in one command at a time and the
  compiler executes it
• Batch
• collection of commands in a file (.bat), executed
  sequentially
• Interpreted
• scripted program contained in a text file,
  compiled and executed on-the-fly, but not stored
  on the computer as an executable file
• Java (Object Code)
• generically compiled code that runs in a Java
  Virtual Machine (JVM)
• .NET Intermediate Language
• generic C program compiled down to machine code
  at run-time
• Compiled
• compiler translates program into object code,
  links object code into a program made up of
  machine-level code, and stores this as an
  executable file

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History of the Programming Process
TREND Evolution from direct manipulation of
machine via machine language, to procedural
languages, to object-oriented languages
TREND Evolution from command-line programming
tools to integrated suites of windows-based tools
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The Olden Days
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Examples of Early Programming

• Machine Language
• 01001010
• 00011100
• Assembly Code (explicit instructions sent to
  registers and interrupts)
• mov DX, 0
• mov AH, 0
• mov AL, 0fh
• int 17h
• int 20h
• Procedural Code (ex C)
• include ltstdio.hgt
• main()
• printf(Hello, World!\n)

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Building Computer Programs

• System development programs
• translate user computer programs written in
  source code into object or machine code
• compiler creates object code
• linker links object code together to create
  executable machine code
• debugger identifies program syntax errors
• interpreter compiles and executes program code
  without creating an executable file

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Examples of Early ProgrammingText Editor and
Command-Line Compiler
Text Editor
Compiler Linker
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Examples of Early ProgrammingInterpreter
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Later Programming

• Integrated Development Environments (IDE)
• Introduced during mid- to late-1980s, when
  windowing systems (such as MS Windows 3.0) became
  available
• Integrated the editing/programming, compiling,
  linking, debugging into one application
• Improved programmer productivity

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Integrated Development EnvironmentPython IDE
Interpreter or Compiler Debugger
Text Editor
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Modern Programming Environments
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Computer-Aided Software Engineering (CASE)

• A tool for programmers, systems analysts,
  business analysts, and systems developers to help
  automate software development
• A combination of software tools and structured
  software development methods
• CASE tools help to improve software quality

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Advantages of CASE Tools

• Improves productivity
• Results in better interaction among users and
  information systems professionals
• Makes easier to create prototypes
• Makers easier to make system design changes as
  circumstances change

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Categories of CASE Tools

• Upper CASE (U-CASE)
• focus primarily on the design aspects of systems
  development
• Lower CASE (L-CASE)
• helps with programming and related activities
• Integrated CASE (I-CASE)
• incorporates both U-CASE and L-CASE functionality
  and provide support for many tasks throughout the
  SDLC

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CASE ToolsVisual Basic IDE
Blank Application
Controls (objects)
Object Attributes to Edit
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CASE ToolsNetBeans IDE (for Java)
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Software Application Frameworks
TREND Software is evolving from stand-alone
applications built from the ground up, into
modern applications build upon frameworks of
existing objects (program code)
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Software ApplicationsHistory

• Historically, applications were built from the
  ground up
• The operating system did not provide resources
  that could be re-used
• Computer code was difficult to re-use

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Software ApplicationsFrameworks

• Today, many companies and open source projects
  have developed frameworks of software objects
  upon which software applications are built
• Microsoft .NET Framework
• Eclipse Framework (eclipse.org/IBM)
• NetBeans (J2EE) Framework (netbeans.org/SUN
  Microsystems)
• Gnome Framework
• KDE Framework

Programs Run On Windows Only Java (Any OS) Java
(Any OS) Linux/BSD Linux/BSD
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Software Application FrameworksThree Levels of
Software
J2EE/XML JMS, MQSeries, etc.
.NET/XML, J2EE/XML JMS, MQSeries, etc.
Message Passing Between Platforms
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Synchonizing Applications
Groove
DCOM, CORBA, Java RMI, JINI
CORBA, Java RMI, JINI
Distributed Object Model
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Application Level
MS Office, WordPerfect Office, Lotus SmartSuite
OpenOffice
Individual Applications
DOS command line, Windows 1, 2, 3, 3.1, Many
others
Desktop Environment
MS Windows 95
GNOME, KDE (Unix/Linux) Aqua (Mac)
Object Model for GUI Properties
COM/COM OLE
X-Windows, GNOME, KDE OpenDoc
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Operating System
Unix, Linux, MacOS X
DOS
MS Windows 95
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Object Oriented Programming
TREND CASE tools are used to build applications
from objects.
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New Programming ConceptsObject Orientation

• Object-Oriented Programming Languages
• Object
• models things in the real world
• Class
• a template or general framework that defines the
  methods and attributes to be included in a
  particular type of object
• Message passing
• allows objects to interact with each other
• Encapsulation
• inaccessibility of data in an object
• Inheritance
• define a class of objects as a special case of a
  more general class
• Polymorphism
• send the same message to several different
  receivers (objects)

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New Programming ConceptsObject Orientation

• The Spread of Object Orientation
• OOA object oriented analysis
• OOD object oriented design
• OOP object oriented programming
• MFC Microsoft Foundation Classes (objects for MS
  Windows)
• DOM document object model
• COM/COM component object model (for
  applications)
• DCOM distributed component object model
  (networked applications)
• CORBA common object request broker architecture
• JINI Suns Java object architecture
• IIOP Internet inter-ORB protocol

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Visual Programming
TREND CASE tools utilize visual programming.
Visual techniques are growing due to their ease
of understanding, and higher programmer
productivity.
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New Programming LanguagesVisual Programming

• Visual Programming Languages
• program within a graphical environment called an
  integrated development environment (IDE)
• allows developers to create applications by
  manipulating graphical images directly
• drag and drop objects or controls onto a
  blank form
• many third-party suppliers of objectpackages
• edit object attributes
• generate interpreted or compiled applications

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New Programming LanguagesVisual Programming

• Examples of Visual Programming Environments
• DELPHI
• CA Visual
• Power Objects
• VisualStudio.NET
• Visual Basic
• Visual C
• Visual J
• Visual FoxPro
• Visual InterDev
• ActiveState Visual Perl (works with MSs .NET
  architecture)
• ActiveState Visual Python (works with MSs .NET
  architecture)

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Internet Programming
TREND Internet programming has gone through the
same types of stages as application programming.
Advanced CASE tools are now available for
developing Internet-based applications.
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Internet-Oriented LanguagesMarkup Languages

• Hypertext Markup Language (HTML)
• standard language the Web uses for creating and
  recognizing hypermedia hypermedia
• hypertext an approach to data management in
  which data area stored in a network of nodes
  connected by links (called hyperlinks)
• uniform resource locators (URLs) represent
  hypermedia links and links to network service
  within HTML

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Internet-Oriented LanguagesMarkup Languages

• Extensions to HTML
• CSS - cascading style sheets
• DHTML - dynamic HTML
• XHTML - next generation HTML
• SMIL (smile) - graphical layout
• WML - WAP markup language

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Internet-Oriented LanguagesMarkup Languages

• Virtual Reality Modeling Language (VRML)
• a file format for describing three-dimensional
  interactive worlds and objects
• represent static and animated objects
• have hyperlinks to other media such as sound,
  video, and image

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Internet-Oriented LanguagesMarkup Languages

• eXtensible Markup Language (XML)
• document delivery across the Net, usually a B2B
  transaction
• organizations agree on an XML structure to
  exchange data
• document type definition (DTD) specifies XML
  structure

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Internet-Oriented Languages Scripting Languages

• WWW Scripting Languages
• Not compiled (JSPs and ASPXs are exceptions)
• Interpreted and executed when called by a Web
  Server, sometimes run in a virtual machine
• Used to build dynamic web sites
• Link web page front end to database back end
• you store SQL code within template file of
  scripts/HTML
• when page requested, transactions performed with
  database or other applications on server
• result of transaction translated into HTML, which
  server sends to your WWW browser

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Internet-Oriented LanguagesScripting Languages

• WWW Scripting Language Examples
• Perl (.pl)
• Python
• Tcl/Tk
• JavaScript
• VBScript
• Active Server Pages (.asp, .aspx)
• Cold Fusion (.cfm)
• PHP (Personal Hypertext Processor)
• probably most common world-wide
• open source works with UNIX/Linux and open
  source databases
• Java Server Pages (.jsp)
• AOLserver Data Pages (.adp freeware, used to
  build Netscape.com and AOL.com)