understanding objects by mark lewis
TRANSCRIPT
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Understanding ObjectsUnderstanding ObjectsObject Oriented Design for Content Specialists
© Mark [email protected]
Part of the Alignment blog series.Download the audioRecording: mp3 & wav
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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
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Take-AwaysTake-AwaysOO defined for Tech WritersExamplesBook RecommendationsAbility to speak and do OO
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AgendaAgendaDefinitions & ConceptsSimple ObjectsComposite ObjectsBehaviors / MethodsResponsibilities / EncapsulationInheritanceContent Management & Re-use
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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
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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.
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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.
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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
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SimpleSimpleCell
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TypesTypesCell Types
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ComplexComplexCell, Organ, System
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Common AttributesCommon AttributesMuscle Cell
– Membrane– Nucleus– Endoplasmic Reticulum (protein factory)– Cytoplasm (fluid medium)– Mitochondria (energy converters)
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Common AttributesCommon AttributesBlood Cell
– Membrane– Nucleus– Endoplasmic Reticulum (protein factory)– Cytoplasm (fluid medium)– Mitochondria (energy converters)
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Common AttributesCommon AttributesNerve Cell
– Membrane– Nucleus– Endoplasmic Reticulum (protein factory)– Cytoplasm (fluid medium)– Mitochondria (energy converters)
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Simple ObjectSimple ObjectcCell “class definition”
– Membrane– Nucleus– Endoplasmic Reticulum (protein factory)– Cytoplasm (fluid medium)– Mitochondria (energy converters)
! Attributes common to all cells
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Common AttributesCommon AttributesEmployee
– Address Line 1– Address Line 2– City– State– Zip– Other Employee specific attributes:
Name, SSN, Gender, Full/Part Time, etc.
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Common AttributesCommon AttributesCompany
– Address Line 1– Address Line 2– City– State– Zip– Other Company specific attributes:
Name, Corp. Type, EIN, etc.
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Common AttributesCommon AttributesVendor
– Address Line 1– Address Line 2– City– State– Zip– Other Vendor specific attributes:
Name, Vendor Type, Govt. Work, etc.
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Simple ObjectsSimple Objects cAddress “class definition”
– Address Line 1– Address Line 2– City– State– Zip
! Classification or categorization of common attributes / characteristics
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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
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Composite ObjectsComposite ObjectsCompany
– Mailing Address– Billing Address– Shipping Address– Company specific attributes
! Re-use of an object
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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
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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
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BehaviorsBehaviors Muscle
– Contract– Relax
Blood– Absorb Oxygen– Release Oxygen
Nerve– Interstate Messaging
! Behaviors are also known as Methods
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PracticePractice
Business Letter
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Composite ObjectsComposite ObjectsCell, Organ, System
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CollectionsCollectionsResume
– Name– Contact Info.– Objective– Skills– Experience– References– Hobbies
! A Collection is a set of objects
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CollectionsCollections
Experience– Date Range– Company– Position– Description
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PracticePractice
Book
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Intermission / SponsorIntermission / Sponsor
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Composite ObjectsComposite Objects
Refrigerator
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Composite ObjectsComposite ObjectsRefrigerator
– Freezer Capacity– Fridge Capacity– Freezer Temp– Frig Temp– Doors– Drawers– Color
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Composite ObjectsComposite Objects cCooling Unit
– Capacity– Temp “current”– Maximum Temp– Minimum Temp– Light– Drawers– Door– Color– Dimensions
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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
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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
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Parent & Child ObjectsParent & Child ObjectsDraw Discussion
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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.
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Common AttributesCommon AttributescCell “class definition”
– Membrane– Nucleus– Endoplasmic Reticulum (protein factory)– Cytoplasm (fluid medium)– Mitochondria (energy converters)
! Attributes common to all cells
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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
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Unique BehaviorsUnique Behaviors Muscle
– Contract– Relax
Blood– Absorb Oxygen– Release Oxygen
Nerve– Interstate Messaging
! Unique attributes and behaviors cause the need for Inheritance
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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
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InheritanceInheritanceEmployee
– Name– SSN– Gender– Contact info– Pay Rate
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InheritanceInheritancecEmployee “class definition”
– Name– SSN– Gender– cAddress
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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.
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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.
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Re-use MapRe-use Map
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Structured ContentStructured ContentEmployee: Definition, Usage, Special Considerations
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Re-use in Reference GuideRe-use in Reference Guide
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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
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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.
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Agenda recapAgenda recapDefinitions & ConceptsSimple ObjectsComposite ObjectsBehaviors / MethodsResponsibilities / EncapsulationInheritanceContent Management & Re-use
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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
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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
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ResourcesResourcesRecommended ReadingObject Technology: A Manager’s Guide
David A. TaylorAddison WesleyISBN: 0201309947
Managing Enterprise Content Ann Rockley – www.Rockley.comNew RidersISBN: 0735713065
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ResourcesResourcesRecommended Website
Ann Rockley presentationswww.Rockley.com
OOD goodieswww.java.sun.com/docs/books/tutorial/java/concepts/
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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
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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
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ContactContactMark Lewisvia LinkedIn
Thank You!© Mark Lewis + ©David Taylor- Object Technology content
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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
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Technical ReviewerTechnical ReviewerManaging Enterprise Content:
A Unified Content Strategy2nd edition
By Ann Rockley & Charles Cooper
– For sale at Amazon.com
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DITAMetrics.comDITAMetrics.comBook & SpreadsheetsPublished by
The Rockley Group
Metrics for Intelligent Content
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ResourcesResources
It’s about metrics …for intelligent content– white papers– discussions – webinar recordings– thought leadership
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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/