- A constructor is a special method which is used to initialize the object at the time of the creation
- Java allows objects to initialize themselves when they are created. This automatic initialization is performed through the use of constructor.
- The constructor is called automatically when an object is created.
- It has the same name as the class name.
- Constructor does not have any return type not even void
- Most classes explicitly define their own constructors within their class definition.
- Default constructor will be supply automatically if no explicit constructor is specified.
- The Box class contains two constructors, one is the default constructors and other is the parameterized constructor that accepts parameter to initialize
- Default constructor will be called for mybox1 while parameterized constructor will be called for mybox2
class Box { double width, height, depth; Box() { Height=width=depth=0; } Box (double h,doublew,double d) { Height = h; width = w; depth = d; } double volume() { return width*height*depth; } } classBoxDemo { public static void main (String args[]) { doublevol; Box mybox1 = new Box (); Box mybox2 = new Box (10,20,30); vol = mybox1.volume (); System.out.println (“Volume is: -“+vol); vol = mybox2.volume (); System.out.println (“Volume is: -“+vol); } }