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syntactic unit > access unit > constructor

constructor
subject			fact

constructor	always have the same name as the class
	can be overloaded using method name overloading
	can call another constructor in the same class, instead of the superclass's zero-parameter constructor, by adding a new statement (as the first statement in the constructor) consisting of the keyword this followed by an argument list
	can call another constructor in the superclass, instead of the superclass's zero-parameter constructor, by adding a new statement (as the first statement in the constructor) consisting of the keyword super followed by an argument list
	can not be called directly
	can not return a value
	can use a constructor of the class's superclass with a super() call
	has definition A procedure that is called whenever a new object is created
	does not have a return type
	does not have a return type since it does not return a value
	does not return a value
	facilitates data abstraction
	has the same name as its class
	has example // Example of creation of an account with an initial balance public Account(String accountHolder, float initialBalance) { this.accountHolder = accountHolder; balance = initialBalance; opened = new Date(); } //Example of creation of an account with no initial balance public Account(String accountHolder) { this.accountHolder = accountHolder; balance =0.0; opened = new Date(); }
	has example //Example of constructor for the class Stack public Stack() { items = new Vector(10); }
	has purpose to initialize the instance variables of a newly created object and perform any other needed initialization
	has typically 1 or more arguments that determine some of the values of the variables of the class
	is not a member
	is not a method
	is a subtopic of Constructors
	is called when the new operator is used to create an instance of a class
	is not inherited by a subclass
	is part of class
	is a kind of access unit
	may have access modifier public or private or protected
	normally calls the zero-parameter constructor in the direct superclass first
	provides a way to initialize a new object
access unit	has access mode
syntactic unit	has syntax rule bold = mandatory italic = non-terminal normal font = optional

Kinds of constructor :

• constructor with no parameters (3 facts)
• default constructor (4 facts) - A constructor that is automatically provided by the runtime system for any class that contains no explicit constructors

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