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member > instance member > instance variable

instance variable (data member, field, object variable)
subject			fact

instance variable	is a synonym of data member
	is a synonym of field
	can be inherited
	can be accessed by all methods of its class
	can be made private to prevent direct access to instance variable - accessor methods should be used instead to protect data abstraction
	has definition A data item present in all the instances of a class, normally used to implement associations and attributes
	has definition Any item of data that is associated with a particular object.
	implements an attribute or an association
	is part of an object
	is a subtopic of Members
	is defined by an instance variable definition
	is a kind of instance member
	is a kind of member variable
	maintains part of its object's state
	refers to an object or a primitive
	should be as private as reasonably possible - almost never make an instance variable public
	should be placed in a class such that there is no needless duplication of it, and such that it is useful in all the subclasses of the class in which it is defined
	to refer you join the name of the variable with a dot to the instance variable name. Example: variableName.instanceVariableName
	is a synonym of object variable
member variable	can be declared anywhere in a class outside of a method
	can be initialized by an assignment statement
	is a member of a class or an object
	is accessible to the code in its class
variable	can contain different classes of objects depending on the type of the variable
	can contain only values that are of the same type as the variable or a subtype of the variable's type
	can have an interface as its type which means that, with the variable, you can invoke any operation supported by the interface
	has 1 value at any one time which is the object or class or primitive datum that it refers to
	has 1 name
	has scope which is the block in which it is declared
	has type
	has lifetime which is the time its block is being executed
	has purpose to refer to an object or a class or a primitive datum
	has scope
	has part value
	is declared by giving the data type followed by the name of the variable
	is destroyed in the block where it is declared
	may have access modifier public or private or protected
	should have comment if it is non-obvious
access unit	has access mode
syntactic unit	has syntax rule bold = mandatory italic = non-terminal normal font = optional

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