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facade comparison table

Subject	have solution	have references	have context	have forces	have problem	has definition	is a subtopic of	is a kind of	is an instance of
design pattern		one or more references which indicate who developed or inspired a pattern	a context	one or more forces	a sentence or two explaining the main difficulty being tackled	A pattern useful for the design of software	6.1 - Introduction to Patterns	pattern
facade	Create a special class, called a «Facade», which will simplify the use of the package. The «Facade» will contain a simplified set of public methods such that most other subsystems do not need to access the other classes in the package. The net result is that the package as a whole is easier to use and has a reduced number of dependencies with other packages. Any change made to the package should only necessitate a redesign of the «Facade»class.	one of the Gang of Four patterns.	html> Often, an application contains several complex packages. A programmer working with such packages has to manipulate many different classes	html> It is hard for a programmer to understand and use an entire subsystem - in particular, to determine which methods are public. If several different application classes call methods of the complex package, then any modifications made to the package will necessitate a complete review of all these classes.	How do you simplify the view that programmers have of a complex package?	A pattern in which you create a class that provides a simplified interface to a package	6.9 - The Facade Pattern		design pattern

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