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| == '''Object Oriented Design''' ==
| | <big>'''Welcome to the PG MediaWiki!!'''</big> |
| | | * [[ECE633]] |
| | | * [[CSC 379]] |
| ''Object-oriented design is a programming paradigm that uses "objects" and their interactions to design computer programs. It is based on several techniques, including encapsulation, modularity, polymorphism, and inheritance.''
| | * [[CSC/ECE 506 Fall 2007]] |
| | | * [[CSC/ECE 517 Fall 2007]] |
| | | * [[KCU]] |
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| == The Software Life Cycle ==
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| ''The development of software is usually broken down into five parts: Analysis, Design, Implementation, Testing, and Deployment.''
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| <br>
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| ::'''Analysis'''- decision-making process in which a decision is made on what the project is suppose to accomplish.
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| ::'''Design'''- the plan is developed for how the system will be implemented.
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| ::'''Implementation'''- the program is written and compiled to implement the classes and methods that were decided on in the design.
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| <br>
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| ::'''Testing'''- tests are run to verify that the program works correctly.
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| ::'''Deployment'''- users install program and use it for its intended purpose
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| <br>
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| == Classes ==
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| While programming in an object-oriented way, you must:
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| <br>
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| :*''Discover classes''
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| :*''Determine the responsibilities of each class''
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| :*''Describe the relationships between the classes''
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| <br>
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| <blockquote>
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| A class represents a set of objects with the same behaviors. Some entities should be represented as objects, <br/>
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| and others as primitive types. An example would be of the decision for an address to be a object of an address <br/>
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| class, or simply a string. This decision depends on what your program needs to complete its tasks. Not all <br/>
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| classes can be discovered in the analysis phase, and some of the classes that you need may already exist, <br/>
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| either in the standard library or in a program that you devloped previously.</blockquote>
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| <br>
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| <br>
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| == Relationships Between Classes ==
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| === Inheritance ===
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| ::*Inheritance is a relationship between a more general class (the superclass) and a more specialized class (the subclass)
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| ::*This relationship is often described as the "is-a" relationship
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| ::*Examples include:
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| ::::Every truck is a vehicle
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| ::::Every savings account is a bank account
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| ::::Every circle is an ellipse
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| <br>
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| :::[[Image:ferrari.jpg]]
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| <br>
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| === Aggregation vs. Association ===
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| :*An '''aggregation''' is a set of objects that make up a unit, also known as a "has-a" relationship. An example of aggregation is:
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| :::[[Image:Aggregation1.jpg]]
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| <br>
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| :*An '''association''' is two or more objects that work together, but one is not part of another. An example of association is:
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| <br>
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| :::[[Image:bank.jpg]]
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| <br>
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| == Learning Exercise ==
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| <br>
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| The idea behind this Restaurant O-O Design Game is to
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| :* Decide which elements are classes - Nouns
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| :* Determine the responsibilities (methods) of each class - Verbs
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| :* Describe the relationships between the classes
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| :* Create a "CRC Card" for each class on the provided flash cards.
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| ::: CRC Stands for "Classes, Responsibilities, and Collaborators"
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| Try organinzing classes so that a common superclass can take care of some responsibilities.
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| :* Team members should find the four main classes they think should exist in a small restaurant.
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| ::: This means making a list of nouns and choosing the four most practical candidates.
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| ::: Write out one class per index card.
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| :* Teams should write at least one responsibility for each class and come up with two total collaborators.
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| ::: Find one important task a restaurant would need to complete for each class, and write it on the CRC Card.
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| ::: Ask your team if this task needs help from other classes, and write this collaborator on the index card.
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| <br>
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| <br>
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| :::An example of a completed CRC Card:
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| :::::[[Image:indexcard.jpg]]
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| <br>
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| <br>
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| == References ==
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| <br>
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| ::*Java Sun - http://java.sun.com/
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| <br>
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| ::*Java Net - http://java.net
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| <br>
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| ::*Object-Oriented Programming - http://objc.toodarkpark.net/oop.html
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| <br>
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