Head First Design Patterns by Eric Freeman and Elisabeth Freeman provides a quick overview of the Visitor Pattern in its appendix. Pluralsight's Design Patterns Library course has a module on the Visitor Pattern from John Sonmez. For the Visitor to be able to perform its operation on the elements of the data structure, it needs to be able to call a method on each element. In the Visitor Pattern…
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Head First Design Patterns by Eric Freeman and Elisabeth Freeman provides a quick overview of the Prototype Pattern in its appendix. Pluralsight's Design Patterns Library course has a module on the Prototype Pattern from John Sonmez. The Prototype Pattern is all about making a copy of or cloning an existing object instead of newing up an object. Sonmez makes the comparison: if you need a second…
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Head First Design Patterns by Eric Freeman and Elisabeth Freeman provides a quick overview of the Memento Pattern in its appendix. Pluralsight's Design Patterns Library course has a module on the Memento Pattern from Steve Smith. The job of the Memento is to save the important state of an important object in a system, in order to acheive that undo-redo functionality. The Memento Pattern can be…
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Head First Design Patterns by Eric Freeman and Elisabeth Freeman provides a quick overview of the Mediator Pattern in its appendix. Pluralsight's Design Patterns Library course has a module on the Mediator Pattern from Donald Belcham. The principles of object-oriented design tell us that tight coupling is bad. So in a system with many objects all working together and interacting with one another…
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Head First Design Patterns by Eric Freeman and Elisabeth Freeman provides a quick overview of the Interpreter Pattern in its appendix. Pluralsight's Design Patterns Library course has a module on the Interpreter Pattern from John Sonmez. Overview The "language" part of the definition above can be applied to practically anything that functions as a means of communication - spoken languages…
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Head First Design Patterns by Eric Freeman and Elisabeth Freeman provides a quick overview of the Flyweight Pattern in its appendix. Pluralsight's Design Patterns Library course has a module on the Flyweight Pattern from Niraj Bhatt. If an application has many instances of a class where all of the logic and controls between them are identical, this is a good sign that the Flyweight Pattern could…
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Head First Design Patterns by Eric Freeman and Elisabeth Freeman provides a quick overview of the Chain of Responsibility Pattern in its appendix. Pluralsight's Design Patterns Library course has a module on the Chain of Responsibility Pattern from Robert Horvick. The Chain of Responsibility Pattern is essentially a chain of objects that, depending on the type of message, handle the message or…
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Head First Design Patterns by Eric Freeman and Elisabeth Freeman provides a quick overview of the Bridge Pattern in its appendix. Pluralsight's Design Patterns Library course has a module on the Bridge Pattern from John Sonmez. The Bridge Pattern's goal is to decouple an implementation and an interface such that abstraction and implementation can be altered independently. Structure In the Bridge…
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Head First Design Patterns by Eric Freeman and Elisabeth Freeman gives a pretty good overview of the MVC Pattern in its twelfth chapter. Pluralsight's Design Patterns Library course has modules on related patterns: MVP from David Starr, and MVVM from Brian Lagunas. Pluralsight also has some great courses on applying MVC, like this step-by-step tutorial from Gill Cleeren. Microsoft provides a good…
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Head First Design Patterns by Eric Freeman and Elisabeth Freeman gives a pretty good overview of the Proxy Pattern in its eleventh chapter. Pluralsight's Design Patterns Library course has a module on the Proxy Pattern from Steve Smith. At its most basic level, the Proxy Pattern is very simple: it provides a subject interface which is implemented by both the proxy and the concrete subject. In many…
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