News Feed
Sections




News Archive
Looking for more information on how to do PHP the right way? Check out PHP: The Right Way

NetTuts.com:
SOLID Part 3 - Liskov Substitution & Interface Segregation Principles
January 27, 2014 @ 11:51:30

On NetTuts.com today they've continued their series covering the SOLID development principles with the next letter in the acronym - "L". It stands for the Liskov Substitution & Interface Segregation Principles. The tutorial also talks some about the "Interface Segregation Principle" as they go hand-in-hand.

The concept of this principle was introduced by Barbara Liskov in a 1987 conference keynote and later published in a paper together with Jannette Wing in 1994. Their original definition is as follows: "Let q(x) be a property provable about objects x of type T. Then q(y) should be provable for objects y of type S where S is a subtype of T." [or more simply] "Subtypes must be substitutable for their base types."

They include some example PHP code showing a base "Vehicle" class and first an example of doing it correctly (with the Template design pattern) and an example of an incorrect method, complete with tests. They then get into the Interface Segregation Principle, an interface that can be depended on to use the module, with the same car-related examples.

0 comments voice your opinion now!
solid design principles liskov substitution interface segregation

Link: http://net.tutsplus.com/tutorials/php/solid-part-3-liskov-substitution-interface-segregation-principles/

blog comments powered by Disqus

Similar Posts

Smashing Magazine: Upcoming Web Design and Development Conferences in 2010

DevShed: Using the Memento Pattern with a File Reading Class

Lukas Smith: Good design is no excuse for wasting time

DZone.com: SOLID for packag...err, namespaces

Adam Jensen's Blog: Spades and the Strategy Pattern


Community Events





Don't see your event here?
Let us know!


package community version interview security update symfony framework tool podcast laravel introduction library install language opinion series voicesoftheelephpant composer release

All content copyright, 2014 PHPDeveloper.org :: info@phpdeveloper.org - Powered by the Solar PHP Framework