CSC 480Software Engineering

Lab 5 – Abstract Factory PatternOct 30, 2002

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The Abstract Factory Pattern

Intent – provide an interface for creating families of related or depended objects without specifying their concrete classes

AKA Kit Like other creational patterns, this pattern can

help to avoid hard-coding the way in which objects need to be created

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Design Pattern Space

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Structure – an illustration

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Application – pluggable look-and-feel

Support multiple look-and-feel user interfaces, such as Windows, Motif, Macintosh Specify the selected look-and-feel in client programs The corresponding GUI factory will be returned to

generate graphical components in the requested laf In Java, this is accomplished at the system level

UIManager.setLookAndFeel(plafName);

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Look-and-Feel Alternatives

Windows

Motif

Metal (swing’s default)

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Application in This Lab

A GardenMaker Factory Garden varieties: annual, perennial, vegetable Common concerns

What are good center plants? What are good border plants? What do well in partial shade?

Plants With a name Other properties can be added

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Major Classes

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Sample Results

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Consequences Benefits

It isolates concrete classes at the client level A factory encapsulates the responsibility and the process of

creating product objects. Clients are isolated from implementation classes

It makes exchanging product families easy – the concrete factory is used once

It promotes consistency among products Liabilities

supporting new kinds of products is difficult