From Design Patterns (Gamma et al)‏ Presented by David Kemp Melbourne Patterns Group

Specify the kinds of objects to create using a prototypical instance, and create new objects by copying this prototype. Design Patterns, Gamma et al, Chapter 4.

Creational Patterns Abstract Factory Builder Factory Method Prototype Singleton

Abstract Factory

Builder

Factory Method

Prototype

Singleton

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Alternative to Factory Method and Abstract Factory. Can be used to implement Abstract Factory. To avoid building a class hierarchy of factories. Can be used when loading classes dynamically Often can use class objects instead.

Alternative to Factory Method and Abstract Factory.

Can be used to implement Abstract Factory.

To avoid building a class hierarchy of factories.

Can be used when loading classes dynamically

Often can use class objects instead.

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Add/Remove prototypes at runtime. Specify new prototypes by varying data. Specify new prototypes by varying structure. Less classes (less sub-classing!)‏ Dynamic class loading.

Add/Remove prototypes at runtime.

Specify new prototypes by varying data.

Specify new prototypes by varying structure.

Less classes (less sub-classing!)‏

Dynamic class loading.

Discussion Factory Method: delegate to subclasses. AbstractFactory, Builder, and Prototype: delegate to another class. Prototype: reduces the total number of classes. Builder: Good when construction logic is complex.

Factory Method: delegate to subclasses.

AbstractFactory, Builder, and Prototype: delegate to another class.

Prototype: reduces the total number of classes.

Builder: Good when construction logic is complex.