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design principle comparison table

Subject	make	state	have benefits	assume that	involve	has definition	accomplish by	have goal	is a subtopic of	have advantage	mean
anticipating obsolescence				changes will inevitably occur in the technology a software system uses and the environment in which it runs			Avoiding the use of early releases of technology Avoiding the use of software libraries that are specific to particular environments Avoiding the use of undocumented features or little-used features of software libraries Avoiding the use of reusable software or special hardware from smaller companies, or from those that are less likely to provide long-term support Using standard languages and technologies that are supported by multiple vendors		9.2 - Principles Leading to Good Design		planning for changes in the technology or environment so the software will continue to run or can be easily changed
decreasing coupling									9.4 - Software Architecture		decreasing the number of dependencies between packages as much as possible
designing for flexibility					actively anticipating changes that a design may have to undergo in the future and preparing for them		Reducing coupling and increasing cohesion which allows you to more readily replace part of a system Creating abstractions - this allows new extensions to be easily added Not hard-coding anything Using reusable code and making code reusable		9.2 - Principles Leading to Good Design
designing for portability							avoiding the use of facilities that are specific to one particular environment	the ability to have the software run on as many platforms as possible	9.2 - Principles Leading to Good Design
designing for testability							ensuring that all the functionality of the code can by driven by an external program, bypassing a graphical user interface		9.2 - Principles Leading to Good Design
divide and conquer			Separate people can work on each part. The original development work can therefore be done in parallel An individual software engineer can specialize in his or her component and become expert at it Each individual component is smaller, and therefore easier to understand When one part needs to be replaced or changed, it can hopefully be done without having to replace or extensively change other parts			The principle of dividing something large into smaller units, so it can be dealt with more easily			9.2 - Principles Leading to Good Design
increasing cohesion	a module easier to understand and change	that you should divide things into smaller chunks intelligently; divide things up, but keep things together that belong together							9.2 - Principles Leading to Good Design		ensuring that a package only has related classes
increasing reusability							generalizing your design as much as possible increasing cohesion reducing coupling increasing abstraction designing your system to contain hooks simplifing your design as much as possible		9.2 - Principles Leading to Good Design
keeping the level of abstraction high									9.2 - Principles Leading to Good Design	it allows you to understand the essence of a subsystem and make important decisions without knowing unnecessary details
reducing coupling									9.2 - Principles Leading to Good Design
reusing existing designs and code where possible									9.2 - Principles Leading to Good Design	it allows you to take advantage of the investment you or others have made in reusable components

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