Notes from 55th International STC Conference
Philadelphia, Pennsylvania, June 1-4, 2008

Introduction to Java™ Concepts for Non-Programmers

Elsie A. Sanders, Intervoice, Inc.

Sanders has made numerous trips to the winners’ circle in STC Online Help competitions, including a Distinguished Award in a 2008 competition for her Intervoice Banking 4.0, Installation Guide. She used metaphor very adroitly to explain a highly technical subject to a lay audience.

Session Description: Increasingly, developers and programmers are using the Java language and object-oriented programming. This session introduces non-programmers to basic concepts and provides strategies for further study and career marketability.

• Computers today
   
• 50M U.S. adults bank online
• 3,000 credit card transactions per minute
• Significant events
   
• Object-oriented programming
• Java language
• Object-oriented programming: what is it?
• And what is an Object?
• Example: automated flood warning system sends out telephone message en masse and redials numbers where it gets an answer machine (or no answer)
• PersonalizeIt... caller repeatedly asking for checking account balance is given option to have it come up automatically as soon as the caller’s number is recognized by the system
• Even non-experts need to know basic nomenclature such as Objects and Classes so they can use the system optimally
• What is an Object? Used elephant metaphor.
• Commands (e.g., traffic light)... must be precise
   
• Turn off all of the lights
• Turn on the red light
• Wait for 60 seconds
• Turn off the red light
• Turn on the green light... etc.
• Analogy for object-oriented programming: Moving kitchen from outside (open fireplace) to inside (enclosed, vented coal stove)
• Procedural programming vs. object-oriented programming
• The Java language forced the programmer to take an object-oriented rather than a procedural approach
• Objects have characteristics (nouns) and behaviors (verbs)
   
• Scroll bar
• Menu bar
• Garbage can
• Many objects interacting
• Object-oriented programming (OOP), object-oriented design (OOD), and Java were ideal for the Internet, resulting in explosive growth
• Single sourcing, content management, or DITA in essence reduce content to “objects” (chunks of data)
• Writing code in capsules (objects) allows reuse
• Shopping cart is an Object and more (the icon connotes the concept of buying multiple objects, paying before leaving, etc.)
• Three elements of an Object
   
• Name: shoppingCart
• Characteristics: nouns: text, icon, color, shape
• Behaviors (methods): getOrderItem, AddToOrder, getQuantity, addToCart
• Object is a chunk of code that creates the characteristics and performs the behaviors
• Action plan for session (informational overview for general user to detailed study for practictioners)
   
• General framework/mental model of what Java and OOP/OOD are
• Classes and objects
• Single-sourcing, content modeling, DITA
• Application Programming Interface (API) documentation: toughest
• Resources on STC site:
   
• Ten pages of notes:
  http://www.stc.org/edu/55thConf/download.asp?ID=95
• Two pages of references for beginners:
  http://www.stc.org/edu/55thConf/download.asp?ID=96
• Handout
   
• OOP terminology
• OOP’s power
• JavaTM language
• Core concepts
   
• Objects and Classes
• Object-oriented programming
• Java language basics
• Packages: Java has 100s of packages with over 5,000 classes
• This led to an extension called Javax, JApplets, etc.
• Packages have language and utilities
• Class is a template
   
• Easier
• Faster
• Consistent
• Reusable
• A class is also a blueprint; from this, the objects (houses) are created. Variations like # of rooms, roof color, etc., can be accomplished by mods to the class blueprint
• Programmer seeking a language goes to language “shelf” in Java and has 32 classes (blueprints) to choose from (capsules of already written code: anywhere from a page to a hundred pages), lessening the amount of detailed new code to be generated (much more cost effective)
• Objects: shirt analogy. Basic blueprint, colors and patterns change
• Objects: cookie cutter analogy (repetition of characteristics)
• Class is like a recipe: ingredients, procedures (can make many different foods)
• Package > class/recipe
• You cannot make an Object without creating a Class. Example: Auto dealer wants online shopping capability where viewer can “build” a car
   
• Keywords – 50 in Java
• Object
• ClassBlueprint
• Constructor ( )
• Car myConvertible; myConvertible = new Car ( );
• Objects can be created from scratch (new code), but reuse of as many functions as possible speeds the process and reduces cost
• CarClass: characteristics and behaviors (methods): specific objects are created by selecting characteristics and behaviors
• Objects allow you to test it, debug it, reuse it, and modify it
• Classes: easier to use, faster, consistent, reuse, some code can be hidden to user, programmer can change hidden code.
• Advanced OOP has 4 key aspects: Abstraction, encapsulation, inheritance, and polymorphism
• Abstraction: a little like abstract art; details are left out, artist drives for the “essence.” Programmers group code in little “models” or templates, minimizing the impact of changes
   
• Control complexity of code
• Reduce amount of code
• Identify framework of code
• Determine relationships
• Encapsulation: hides some of the “engine code” from the user (analogy: visitor sees dining room, cook goes into kitchen to get food): Java keywords are “private” and “public”
   
• Faster to develop
• Fewer bugs
• Allows programmer to change the code
• Others can’t change what’s inside
• Inheritance: 200 lines of code, hardware engineers, software engineers, test engineers. Each subset inherits the characteristics of the class above it.
• Polymorphism: Animal speak () click on dog and it barks; click on cat and it meows.
• Java powers
   
• More than 4.5 devices
• Over 800M PCs
• Over 1.5B million mobile phones and other hand-held devices
• 2.2B smart cards
• Web cams, games, car navigation systems, medical devices, parking payment
• Java classes have grown from 250 classes in 1995 to 5,000 in 2004 – now leading to Javax
• Of the predefined 5,000 classes, 28 do 90% of the work: if you’re dabbling in it, learn those 28 first
• OOP and Java
   
• Object-oriented programming
• Classes and objects
• Basic Java code