SUGCON Europe 2015 presentation on Design Patterns in Sitecore.

1. Attain Clean Code in
Sitecore Solutions using
Design Patterns
Mike Reynolds
Hanson Dodge Creative
@mike_i_reynolds
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2. What’s a Design Pattern?
• “General reusable solution to a commonly occurring problem“
• http://en.wikipedia.org/wiki/Software_design_pattern
• Describes how to solve a problem
• Can be across different contexts
• Provides a common language for developers
• Is not a cookie-cutter code solution!
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3. Design Patterns: History
• Proposed by Christopher Alexander (1970s)
• A Pattern Language: Towns, Buildings, Construction
(http://amzn.to/1BtaaIH)
• Kent Beck and Ward Cunningham applied the concept to
programming (1987)
• Presented results at Object-Oriented Programming, Systems,
Languages & Applications (OOPSLA)
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4. Design Patterns: History
• Gang of Four (GoF) Book (1994)
• Design Patterns: Elements of Reusable Object-Oriented Software.
(http://amzn.to/UPNN2F)
• Erich Gamma, Richard Helm, Ralph Johnson, and John Vlissides
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5. Design Patterns: Examples
• Adapter
• Decorator
• Composite
• Chain-of-responsibility
• Null Object
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6. Adapter Pattern
• Allows the interface of an existing class to be used from another
• A “wrapper”
• Makes existing classes work with others without modifying their
source code
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7. Adapter Pattern
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8. Decorator Pattern
• Encapsulates an object with the same interface
• Also a “wrapper”
• Adds/removes/alters functionality on the inner instance
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9. Decorator Pattern
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10. Composite Pattern
• Encapsulates a collection of objects with the same interface
• Treats the entire collection as one object
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11. Composite Pattern
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12. Chain-of-responsibility Pattern
• Composed of command objects and a series of processing
objects
• Each processing object executes specific command objects
• Processing objects are chained together
• think linked list
• Processing objects are invoked in a cascading manner
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13. Null Object Pattern
• Represents the “null” state of an object
• Provides methods with no behaviour
• Removes the need of client code performing null checks
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14. Learn More!
• Recommend Books
• http://amzn.to/UPNN2F
• http://amzn.to/1ppJHeH
• http://amzn.to/1EZEa3z
• http://amzn.to/1bSAYsh
• Blog posts
• http://bit.ly/1E7J7JO
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15. Get In Touch!
Blog: http://sitecorejunkie.com
Twitter: @mike_i_reynolds
LinkedIn: http://linkd.in/1Csu1N8
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16. Questions?
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17. Thank you
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