# IT:AD:Patterns:Builder #



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Builders focus on constructing and configuring *complex* *aggregate* objects.


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## Notes ##

Designs often start simply, only needing a [[IT/AD/Patterns/Factory/]], and evolve towards an [[IT/AD/Patterns/Abstract Factory/]], [[IT/AD/Patterns/Prototype/]] or [[IT/AD/Patterns/Builder/]] as the developer discovers where more flexibiility is required.

Builders are good candidates for a fluent interface.



Builder focuses on constructing a complex object step by step. Abstract Factory emphasizes a family of product objects (either simple or complex). Builder returns the product as a final step, but as far as the Abstract Factory is concerned, the product gets returned immediately.
Builder often builds a Composite.