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variable comparison table

Subject	declare by	have	be	cause	add to	access through	is a synonym of	is a subtopic of	implement	overuse	group	hide	have purpose	use in	access by	use	has definition	help	represent	use by	implement as	share by	identify by	contain
attribute		an implicit internal structure	private		a model unless it is relevant to the application - it will be needed to implement some requirement	public methods so that attributes are only given valid values and so that you can change the internal design of the class without affecting how users of the class interact with it		9.2 - Principles Leading to Good Design			the pieces of data that describe some entity, so that programmers can manipulate that data as a unit	the details of data		the analysis and design stage before it is known how the attribute will be implemented			A simple data item present in all the instances of a class	a programmer to cope with the complexity of data	a variable number of things		an instance variable in Java		looking at the description of the system and searching for information that must be maintained about each class	different classes of objects depending on the type of the variable
class variable		a value that is shared by all instances of a class					static variable	The Basics of Java					storing: Default or 'constant' values that are widely used by methods in a class Lookup tables and similar structures used by algorithms inside a particular class				A data item present in a class that is shared by all instances of that class					all instances of the class		different classes of objects depending on the type of the variable
global variable		comment if it is non-obvious		common coupling				9.2 - Principles Leading to Good Design						older programming languages			A variable that is accessible from all procedures in the system, or in the scope of just a specific set of modules (e.g. a Java package).							different classes of objects depending on the type of the variable
instance variable		comment if it is non-obvious	as private as reasonably possible - almost never make them public				field	2.3 - Instance Variables	an attribute or association								A data item present in all the instances of a class, normally used to implement associations and attributes							different classes of objects depending on the type of the variable
Java variable	giving the data type followed by the name of the variable	an interface as its type which means that, with the variable, you can invoke any operation supported by the interface	as private as possible					The Basics of Java							other variables and methods in any class in the same package by default									different classes of objects depending on the type of the variable
reference		comment if it is non-obvious						2.3 - Instance Variables									A variable that refers to an object							different classes of objects depending on the type of the variable
variable declared as a non-primitive data type		comment if it is non-obvious						The Basics of Java								the name of a class as their type				calling methods or accessing the object's instance variables				an instance of a class
variable declared as primitive data type		comment if it is non-obvious						The Basics of Java																object in the sense that its contents is not an instance of any class

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