/* This program demostrates writing standalone classes in Java.
 * We are designing a class for a circle, that contains data about its radius and color.
 * We also write a method to find the area of the circle and one to print the required data.
  */
import java.util.Scanner;
class Circle
{
	//data attributes
	double radius;
	String color;
	static final double PI =3.14;
	//This variable counts the number of objects declared so far
	static int count =0;
	
	/* constructors
	 * constructors are methods that are used to initialize the data attributes of an object.
	 * They are always public, have the same name as the class and have no return type.
	 * They are automatically invoked when the object is declared.
	 */
	//default constructor
	public Circle ()
	{
		radius = 10;
		color ="Red";
		count++;
	}
	
	//parameterized constuctor
	public Circle(double r, String c)
	{
		radius = r;
		color = c;
		count++;
	}
	
	/*accessors and mutators
	 * Accessors, or get methods retrun the value of an attribute.
	 * Mutators, or set methods change the value of an attribute.
	 * They are one line public methods that contain the name of the attribute in their name.
	 * There should be one of each per atribute.
	 */
	public double getRadius()
	{
		return radius;
	}
	
	public String getColor()
	{
		return color;
	}
	
	public void setRadius(double r)
	{
		radius = r;
	}
	
	public void setColor(String c)
	{
		color =c;
	}
	//This method prints all the pertinent data
	void print()
	{
		System.out.println("Radius: " +radius+"\nColor: "+color+"\nArea: "+findArea());
	}
	//To calculate the area of the circle.
	double findArea()
	{
		return PI*radius*radius;
	}
	
	public static void main(String [] args)
	{
		Scanner input = new Scanner(System.in);
		
		//declare objects
		Circle c1 = new Circle(); //default constructor invoked
		Circle c2 = new Circle(12.5, "Green");//parameterized constructor invoked.
		//calling the print method
		// print is an instance method and should be called using the object
		c1.print(); 
		c2.print();
		
		System.out.println("Enter the radius :");
		double r = input.nextDouble();
		System.out.println("Enter the color:");
		String col = input.next();
		
		//change the values of c1's attributes to the user given values using the mutators
		c1.setRadius(r);
		c1.setColor(col);
		
		c1.print();
		
		System.out.println("There are "+count+" objects");
	}
}