Understanding Objects by Mark Lewis

Understanding ObjectsUnderstanding ObjectsObject Oriented Design for Content Specialists

© Mark Lewismlewis@ditametrics.com

Part of the Alignment blog series.Download the audioRecording: mp3 & wav

What & WhyWhat & Why For Software Development

– facilitates re-use of code– single point of maintenance– data hiding or encapsulation– API = Application Programming Interface

For Technical Writing– facilitates re-use of content– single point of maintenance– CMS = Content Management System– AuthorIT– XML

Take-AwaysTake-AwaysOO defined for Tech WritersExamplesBook RecommendationsAbility to speak and do OO

AgendaAgendaDefinitions & ConceptsSimple ObjectsComposite ObjectsBehaviors / MethodsResponsibilities / EncapsulationInheritanceContent Management & Re-use

Definitions & ConceptsDefinitions & ConceptsObject

What it is , What it does and How it interacts with other objects

…share a common structure and a common behavior

…has a predictable or fixed relationship with other objects

Definitions & ConceptsDefinitions & ConceptsClass

The definition or blueprint of an Object. Almost interchangeable with “Object”.

AttributeA characteristic of an object. What it is……programming lingo…Also known as a Property.

BehaviorAn activity of an object. What it does/is responsible for……programming lingo…Also known as a Method.

Definitions & ConceptsDefinitions & ConceptsObject

A categorization or classification of things that allows us to organize functionality or information in a way that it may be re-used / re-purposed.

The StrategyThe Strategy

Find the commonality in the “what it is” and “what it does”

Find the commonality in the attributes and behaviors

What is shared?

! The design will depend on your GOALS

SimpleSimpleCell

TypesTypesCell Types

ComplexComplexCell, Organ, System

Common AttributesCommon AttributesMuscle Cell

– Membrane– Nucleus– Endoplasmic Reticulum (protein factory)– Cytoplasm (fluid medium)– Mitochondria (energy converters)

Common AttributesCommon AttributesBlood Cell

– Membrane– Nucleus– Endoplasmic Reticulum (protein factory)– Cytoplasm (fluid medium)– Mitochondria (energy converters)

Common AttributesCommon AttributesNerve Cell

– Membrane– Nucleus– Endoplasmic Reticulum (protein factory)– Cytoplasm (fluid medium)– Mitochondria (energy converters)

Simple ObjectSimple ObjectcCell “class definition”

– Membrane– Nucleus– Endoplasmic Reticulum (protein factory)– Cytoplasm (fluid medium)– Mitochondria (energy converters)

! Attributes common to all cells

Common AttributesCommon AttributesEmployee

– Address Line 1– Address Line 2– City– State– Zip– Other Employee specific attributes:

Name, SSN, Gender, Full/Part Time, etc.

Common AttributesCommon AttributesCompany

– Address Line 1– Address Line 2– City– State– Zip– Other Company specific attributes:

Name, Corp. Type, EIN, etc.

Common AttributesCommon AttributesVendor

– Address Line 1– Address Line 2– City– State– Zip– Other Vendor specific attributes:

Name, Vendor Type, Govt. Work, etc.

Simple ObjectsSimple Objects cAddress “class definition”

– Address Line 1– Address Line 2– City– State– Zip

! Classification or categorization of common attributes / characteristics

Composite ObjectsComposite Objects Employee

– cAddress {Addr 1, Addr 2 ….}– Employee specific attributes

Company– cAddress {Addr 1, Addr 2 ….}– Company specific attributes

Vendor– cAddress {Addr 1, Addr 2 ….}– Vendor specific attributes

! Re-use of an object

Composite ObjectsComposite ObjectsCompany

– Mailing Address– Billing Address– Shipping Address– Company specific attributes

! Re-use of an object

Ease of MaintenanceEase of Maintenance cAddress/cContact (* = new)

– Address Line 1– Address Line 2– City– State– Zip– Voice Phone Number*– Fax Phone Number*– Email*

! Maintenance is reduced to one place

BehaviorsBehaviors cCell “class definition”

– Grow– Reproduce– Intake Nutrients– Output Waste– Send Message

! Behaviors are what an object does & what it is responsible for

! Behaviors common to all cells

BehaviorsBehaviors Muscle

– Contract– Relax

Blood– Absorb Oxygen– Release Oxygen

Nerve– Interstate Messaging

! Behaviors are also known as Methods

PracticePractice

Business Letter

Composite ObjectsComposite ObjectsCell, Organ, System

CollectionsCollectionsResume

– Name– Contact Info.– Objective– Skills– Experience– References– Hobbies

! A Collection is a set of objects

CollectionsCollections

Experience– Date Range– Company– Position– Description

PracticePractice

Book

Intermission / SponsorIntermission / Sponsor

Composite ObjectsComposite Objects

Refrigerator

Composite ObjectsComposite ObjectsRefrigerator

– Freezer Capacity– Fridge Capacity– Freezer Temp– Frig Temp– Doors– Drawers– Color

Composite ObjectsComposite Objects cCooling Unit

– Capacity– Temp “current”– Maximum Temp– Minimum Temp– Light– Drawers– Door– Color– Dimensions

Composite ObjectsComposite ObjectsRefrigerator

– Freezer Section : cCooling Unit– Fridge Section : cCooling Unit

Refrigerator – cCooling Units “collection”

! A composite object is known as a Parent

! An embedded object is known as a Child

EncapsulationEncapsulation cCooling Unit

Behaviors for accessing data. What it is.– GetCapacity / SetCapacity– GetDimensions / SetDimensions– GetTemp “current” / SetTemp– GetColor / SetColorBehaviors that do something. What it does.– DoorOpen / DoorClose– LightOn / LightOff “private”– Draw

! Encapsulation hides the internals of data and behaviors from other objects

! Private behaviors may not be used/called by other objects

Parent & Child ObjectsParent & Child ObjectsDraw Discussion

GlossaryGlossary

Behavior Something that an object does or can do. Some behaviors may be invoked by other objects others are strictly for internal use only.…programming lingo…Also know as a Method. Public methods may be invoked / called by other objects.Private methods may only be invoked / called internally by the object itself.

Common AttributesCommon AttributescCell “class definition”

– Membrane– Nucleus– Endoplasmic Reticulum (protein factory)– Cytoplasm (fluid medium)– Mitochondria (energy converters)

! Attributes common to all cells

Common BehaviorsCommon BehaviorscCell “class definition”

– Grow– Reproduce– Intake Nutrients– Output Waste– Send Message

! Behaviors are what a object can do & what it is responsible for

Unique BehaviorsUnique Behaviors Muscle

– Contract– Relax

Blood– Absorb Oxygen– Release Oxygen

Nerve– Interstate Messaging

! Unique attributes and behaviors cause the need for Inheritance

InheritanceInheritance cMuscleCell : cCell

– Contract– Relax

cBlood : cCell– Absorb Oxygen– Release Oxygen

cNerve : cCell– Interstate Messaging

! An object that inherits from a base object gets all the attributes & behaviors of the base object PLUS any unique attributes & behaviors

InheritanceInheritanceEmployee

– Name– SSN– Gender– Contact info– Pay Rate

InheritanceInheritancecEmployee “class definition”

– Name– SSN– Gender– cAddress

InheritanceInheritance cSalariedEmployee : cEmployee

– Annual Rate– Accrued Vacation, Accrued Sick Time

cHourlyFullTimeEmployee : cEmployee– Hourly Rate– Accrued Vacation, Accrued Sick Time

cHourlyPartTimeEmployee : cEmployee– Hourly Rate

! Look for the common attributes & behaviors. Strategy.

Content ManagementContent Management

A form, slide layout or a skeleton doc provides a template / class design. Different from a WORD template (.DOT) though, for .DOT provides styles only, not structure.

Re-use MapRe-use Map

Structured ContentStructured ContentEmployee: Definition, Usage, Special Considerations

Re-use in Reference GuideRe-use in Reference Guide

From the menu tree, select Payroll, Maintenance, Employee

Employee: An employee is an individual who is performing or has performed work on the company's behalf while on the company's payroll.

Usage: The Employee document is used by time, unit pricing and expense input to record appropriate charges for project and payroll processes. Used for sorting, analyzing, inquiry and reporting purposes.

Employee Code: Provides a unique user-defined employee identifier.

Payroll Master Files – Employee Maintenance Foundation > Master File Setup

Payroll Master Files – Employee Maintenance Foundation > Master File Setup

From the menu tree, select Payroll, Maintenance, Employee, General tab

The General Information tab contains employee-related attributes needed to process the employee in the ABC system

Name: Specifies the legal name of the employee.

Alpha Name: Alphabetical employee name format.

SSN / SIN: Identifies the employee's federal tax identification code such as the U.S. federal Social Security Number or the Canadian federal Social Insurance Number.

Usage: Used for third party payroll system integration.

Company: Specifies the Company for which the employee primarily works. Usage: Used as the Company code for employee related inputs such as time,

unit pricing and expense.

Currency: Specifies the Currency or monetary unit of the employee. Usage: Specifies the Currency in which the employee will be paid for payroll

purposes. An Employee may charge to any Project Currency, but will be paid in their Employee Currency.

Organization: Specifies the Organization for which the employee primarily works.

Usage: Used as the default Organization code for employee related input such as time, unit pricing and expense.

Agenda recapAgenda recapDefinitions & ConceptsSimple ObjectsComposite ObjectsBehaviors / MethodsResponsibilities / EncapsulationInheritanceContent Management & Re-use

The StrategyThe StrategyFind the commonality in the “what it is” and “what it does”

Find the commonality in the attributes and behaviors

What is shared?

! The design will depend on your GOALS

WhyWhy For Software Development

– facilitates re-use of code– single point of maintenance– data hiding or encapsulation– API = Application Programming Interface

For Technical Writing– facilitates re-use of content– single point of maintenance– CMS = Content Management System– AuthorIT– XML

ResourcesResourcesRecommended ReadingObject Technology: A Manager’s Guide

David A. TaylorAddison WesleyISBN: 0201309947

Managing Enterprise Content Ann Rockley – www.Rockley.comNew RidersISBN: 0735713065

ResourcesResourcesRecommended Website

Ann Rockley presentationswww.Rockley.com

OOD goodieswww.java.sun.com/docs/books/tutorial/java/concepts/

GlossaryGlossaryObject “An object corresponds to a concept, abstraction, or thing that can

be distinctly identified. During analysis, objects have attributes and may be involved in relationships with other objects. During design, the notion of object is extended by the introduction of methods and objects attributes. In the implementation phase the notion of object is determined by the programming language."1 “An object is a software bundle of related variables and methods. Software objects are often used to model real-world objects you find in everyday life. 3

Class "A set of objects that share a common structure and a common behavior. A class is an abstraction, which represents the idea or general notion of a set of similar objects."1 “A class is a blueprint or prototype that defines the variables and the methods common to all objects of a certain kind.” 3

Class Description

"Description of the attributes, methods interface and inheritances relationships of a class."1

GlossaryGlossaryAttribute "A set of named values associated with an object or relationship."1

Behavior Something that an object does or can do. Some behaviors may be invoked by other objects others are strictly for internal use only.…programming lingo…Also know as a Method. Public methods may be invoked / called by other objects.Private methods may only be invoked / called internally by the object itself.

Inheritance “A class inherits state and behavior from its superclass. Inheritance provides a powerful and natural mechanism for organizing and structuring software programs. ” 3

Messaging “Software objects interact and communicate with each other using messages. ” 3

ContactContactMark Lewisvia LinkedIn

Andmlewis@ditametrics.com

Thank You!© Mark Lewis + ©David Taylor- Object Technology content

Guest Author: ROI ChapterGuest Author: ROI ChapterDITA 101 2nd edition“Fundamentals of DITA for

Authors and Managers”By the Rockley Group

with Mark Lewis

– For sale at LuLu.com

Technical ReviewerTechnical ReviewerManaging Enterprise Content:

A Unified Content Strategy2nd edition

By Ann Rockley & Charles Cooper

– For sale at Amazon.com

DITAMetrics.comDITAMetrics.comBook & SpreadsheetsPublished by

The Rockley Group

Metrics for Intelligent Content

ResourcesResources

It’s about metrics …for intelligent content– white papers– discussions – webinar recordings– thought leadership

ReferencesReferences1 Object-Oriented Development: The Fusion Method

Coleman, Arnold, Bodoff, Dollin,Gilchrist, Hayes & JeremaesPrentice HallISBN: 0133388239

2 Object Technology: A Manager’s GuideDavid A. TaylorAddison WesleyISBN: 0201309947

3 www.java.sun.com/docs/books/tutorial/java/concepts/