Constructor

• 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);
       }
}