Chapter 9 OOP Object Oriented Programming

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Chapter 9OOP - Object Oriented Programming
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IS 2020
CI 9008 George Zolla
Prof
. Gary Porter
grporter_at_
nps
.navy.mil
Naval Postgraduate School
Monterey, CA
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Instances and Classes

• Class
• formal definition of an object
• Methods Properties
• Analogy - gingerbread man cookie cutter
• Instance (Instantiate)
• one of the set of objects that belongs to a class
• Analogy - any of the gingerbread men cookies

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Object

• Object
• Properties - characteristics of an object
• Methods - action or behavior
• Examples
• Cookie.Flavor Chocolate Property
• Cookie.Crumble Method

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Classes versus objects
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Object-oriented Language

• Encapsulation
• Holds all properties, methods events
• Referred to as data hiding (Private)
• Polymorphism (many shapes)
• Behaviors that are named the same but act
  differently in different classes
• Inheritance (Not in VB)
• create a new class from an existing class.

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Sample class hierarchy
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Employee
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Class hierarchy and instance variables
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