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Advanced Software Development & Engineering
Creational Patterns (II)
Advanced Software Development & Engineering
Structural Patterns
Factory Method
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Simple decision making class that returns one of several possible
subclasses of an abstract base class depending on the data we provided
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Abstract Factory Method
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Builder Pattern
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Prototype Pattern
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Interface to create and return one of several families of related objects
Separates the construction of a complex object from its representation
Describe how classes & objects can be
combined to form larger structures
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Class Patterns: How inheritance can be used to
provide more useful program interfaces
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Object Patterns: How objects can be composed
into larger structures (objects)
Clones an instantiated class to make new instances rather than creating
new instances
Singleton Pattern
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Class of which there can be no more than one instance. It provides single
global point of access to that instance
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Advanced Software Development & Engineering
Structural Patterns II
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Separates an object’s interface from its implementation
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Composite
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Decorator
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Façade
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It’s easy for an unique client to use one abstraction
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Add responsibilities to objects dynamically
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Proxy
Nevertheless, it’s possible that the client may need
multiple abstractions
…and may be it does not know before using them
how many and what!
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A single class that represents an entire subsystem
Flyweight
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Concerned with communication between objects
A tree structure of simple and composite objects
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Match interfaces of different classes
Bridge
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Behavioral Patterns
Adapter
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Advanced Software Development & Engineering
This kind of Patters (observer, blackboard, mediator) will
allow this communication
A fine-grained instance used for efficient sharing
An object representing another object
iCSC 2005
23-25 February 2005, CERN
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Advanced Software Theme
Lecture 2
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