Constructor Definition & Meaning

A constructor initializes an object in object-oriented programming. In many programming languages, a constructor has the same name as the class in which it creates the object. A programmer will typically declare a constructor within the class and then define the data types that make up the ensuing object.

Common types of constructors

Default constructors: what the program automatically inserts if no constructor is defined. This depends on the language, but typically a default constructor sets everything within the new object to its default value (such as 0) and defines no arguments. It can also set default parameters but is still considered a default constructor.

Parameterized constructor: has parameters which identify arguments once a new object is initialized. The program automatically calls a constructor, which a programmer designs with certain parameters.

Copy constructor: creates a new object by making a copy of a preexisting one. Typically these objects must be in the same class.

Conversion constructor: does not have a specific (explicit) declaration; instead, the program implies the declaration. If a constructor is only given one parameter, the program may convert an object to another class or type implicitly. This is also referred to as a converting constructor.

Move constructor: transfers a pointer to different data or assigns the data to another object, instead of using a copy constructor. The data type moves rather than being copied.






Jenna Phipps
Jenna Phipps
Jenna Phipps is a contributor for websites such as Webopedia.com and Enterprise Storage Forum. She writes about information technology security, networking, and data storage. Jenna lives in Nashville, TN.

Top Articles

Huge List Of Texting and Online Chat Abbreviations

From A3 to ZZZ we list 1,559 text message and online chat abbreviations to help you translate and understand today's texting lingo. Includes Top...

How To Create A Desktop Shortcut To A Website

This Webopedia guide will show you how to create a desktop shortcut to a website using Firefox, Chrome or Internet Explorer (IE). Creating a desktop...

The History Of Windows Operating Systems

Microsoft Windows is a family of operating systems. We look at the history of Microsoft's Windows operating systems (Windows OS) from 1985 to present...

Hotmail [Outlook] Email Accounts

  By Vangie Beal Hotmail is one of the first public webmail services that can be accessed from any web browser. Prior to Hotmail and its...

Legacy Code Definition &...

Legacy code refers to source code that has been inherited from a previous...

Unregulated Power Supply Definition...

An unregulated power supply is a system that transforms input voltage into direct...

Cybersecurity Awareness Training Definition...

Cybersecurity awareness training informs employees of the attack surfaces and vectors in their...