Constructors

A constructor  is a method that has the same name as its class (and which has no return value). Three constructors are defined in Program . The purpose of a constructor is to initialize an object. A constructor is invoked whenever a new instance of a class is created using the new operator.

Consider the following sequence of variable declarations:

Complex c = new Complex ();     // calls Complex ()
Complex d = new Complex (2.0);  // calls Complex (double)
Complex i = new Complex (0, 1); // calls Complex (double, double)

Consider the constructor that takes two double arguments, x and y (lines 6-10). This constructor initializes the complex number by assigning x and y to the real and imag fields, respectively.

• The No-Arg Constructor

Copyright © 1998 by Bruno R. Preiss, P.Eng. All rights reserved.