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syntactic unit > access unit > variable > pointer > object reference

object reference (handle, reference)
subject			fact

object reference	is a synonym of handle
	has definition A variable that refers to an object
	has purpose to refer to an object indirectly so the object may be moved or reclaimed
	is a key into the object table
	is a label for a chunk of memory that holds the memory address for a chunk of memory that holds and instance
	is not accessible to the programmer except for the equals method
	is a subtopic of Objects
	is a kind of pointer
	to cascade you prepend a class or package names to a reference with the character '.'
	is a synonym of reference
variable	can be accessed by other variables and methods in any class in the same package by default
	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
	can refer to a particular object, several different objects during the execution of a program, or no object at all
	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 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
	refers to a class or an object or a primitive datum
	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

Kinds of object reference :

• named object reference (1 kind, 7 facts)
• unnamed object reference (3 facts)
• variable reference (2 facts)

Up: pointer