2.  What is SOLID  The S in SOLID  The O in SOLID  The L in SOLID  The I in SOLID  The D in SOLID  Questions

4.  A means to avoid technical debt  Decrease Coupling  Increase Cohesion  Maintainable  Extensible  Testable

5.  Guidelines, NOT LAWS You got to know when to hold’em, know when to fold’em, Know when to walk away and know when to run. -Kenny Rogers

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7. Single Responsibility Principle There should never be more than one reason for a class to change -Uncle Bob

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10. Open-Close Principle Software entities (classes, modules, functions, etc…) should be open for extension, but closed for modification -Uncle Bob

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13. Liskov Substitution Principle Functions that use pointers or references to base classes must be able to use objects of derived classes without knowing it -Uncle Bob

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16. Interface Segregation Principle Clients should not be forced to depend upon interfaces that they do not use -Uncle Bob

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18. Dependency Inversion Principle High level modules should not depend upon low level modules. Both should depend upon abstractions Abstractions should not depend upon details. Details should depend upon abstractions -Uncle Bob

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23.  Martin Folwer – Technical Debt  http://www.martinfowler.com/bliki/TechnicalDebt.html http://www.martinfowler.com/bliki/TechnicalDebt.html  Wikipedia – Coupling  http://en.wikipedia.org/wiki/Coupling_(computer_programming) http://en.wikipedia.org/wiki/Coupling_(computer_programming)  Wikipedia – Cohesion  http://en.wikipedia.org/wiki/Cohesion_(computer_science) http://en.wikipedia.org/wiki/Cohesion_(computer_science)  Robert Martin – The Principles of OOD  http://butunclebob.com/ArticleS.UncleBob.PrinciplesOfOod http://butunclebob.com/ArticleS.UncleBob.PrinciplesOfOod  Derick Bailey – SOLID Principles – Step by step code  https://github.com/derickbailey/presentations-and- training/tree/master/SOLID%20Principles%20- %20Step%20By%20Step%20Code https://github.com/derickbailey/presentations-and- training/tree/master/SOLID%20Principles%20- %20Step%20By%20Step%20Code

24.  Email – twang1978@gmail.comtwang1978@gmail.com  Twitter – @tonycwang  LinkedIn – www.linkedin.com/in/tonycwangwww.linkedin.com/in/tonycwang