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accessor method
subject			fact

accessor method	allows you to include additional computation, for example writing out a message
	can provide access to imaginary instance variable that exist only in the sense that their values can be computed from instance variables that do exist
	has definition A method which returns (getter) or changes (setter, mutator) the state of an object
	facilitates data abstraction
	is a subtopic of Methods
	is a kind of method
	should be provided if you anticipate that the detailed definition of a class may change because this will isolate the effects of potential changes
method	if a method is declared with the same method signature as a method in a superclass then this method overrides the method with the same method signature in the superclass
	if a method may throw a checked expression then the method must have a throws clause that mentions the class of that exception or one of the superclasses of the class of that exception
	when a method is called a piece of memory is allocated for every parameter
	when a method is called and the method's parameter is a reference type then the memory allocated for that parameter holds a copy of the address of the argument
	when a method is called and the method's parameter is a primitive type then the memory allocated for that parameter holds a copy of the parameter itself
	belongs to a class
	can access all instance variables of all objects of its class
	can be inherited by subclasses of its class
	can be accessed by other methods and variables in any class in the same package by default
	can have an array as a parameter - see method parameter
	can use the super method to invoke a method declared in the superclass
	cannot be passed as an argument to a method or constructor
	creates an object by instantiating a class
	does not return a value if it has a void return type
	has part method definition
	has part method signature
	has part a block of implementation code
	implements the behaviour of an object or the behaviour of a class
	is equivalent to the terms "function member" or "member function" which are used in C++
	is equivalent to the terms "routine", "function" or "method" which are used in non object-oriented programming languages
	is part of a class or an object
	may contain empty return statement if it has a void return type
	may have access modifier public or private or protected
	must contain return statement unless it has a void return type
	must define its parameter list
	must define its return type
	overrides a method in a superclass with the same name
	returns a value that is of the return type of the method or a subtype of that type
	should be as private as possible
	should have a comment at its head if the method is non-obvious
	should not be public except for those that will definitely need to be called from outside the package
	should return to its caller from only one place which should be the last statement
	usually hides instance variables, class variables from other objects
access unit	has access mode
syntactic unit	has syntax rule bold = mandatory italic = non-terminal normal font = optional

Kinds of accessor method :

• get method (6 facts) (getter) - A method that returns the value of an instance variable, A method which returns the state of an object
• set method (7 facts) (mutator, setter) - a method that assigns a value to an instance variable, A method which changes the state of an object

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