Indicate what is printed by the following Java code: public class Circle { priva
ID: 3904383 • Letter: I
Question
Indicate what is printed by the following Java code:
public class Circle {
private double radius;
private static int circleCount = 0;
public Circle (double radius) {
circleCount++
this.radius = radius;
}
public double getDiameter() {
return radius * 2.0;
}
public static int getCircleCount() {
return circleCount;
}
}
public class CircleTester {
public static void main(String[] args) {
Circle c1, c2, c3, c4;
c1 = new Circle(1,0);
c2 = new Circle(4,0);
c3 = new Circle(9,0);
c4 = new Circle(16,0);
System.out.println(“c1,c2,c3,c4 diameters => “ + c1.getDiameter() + “ “ + c2.getDiameter() + “ “ + c3.getDiameter() + “ “ + c4.getDiameter());
System.out.println(Circle.getCircleCount()+” circles.”);
}
}
Explanation / Answer
Output
// Program is corrected and comments are inline
class Circle {
private double radius;
// this tracks the number of objects created
private static int circleCount = 0;
// constructor
public Circle (double radius) {
circleCount++; // Incrementing by 1 for each time an object is created
this.radius = radius;
}
// getting the diameter of circle
public double getDiameter() {
return radius * 2.0;
}
// getting the total count of instances
public static int getCircleCount() {
return circleCount;
}
}
class CircleTester {
public static void main(String[] args) {
Circle c1, c2, c3, c4;
// creating 4 objects
c1 = new Circle(1.0);
c2 = new Circle(4.0);
c3 = new Circle(9.0);
c4 = new Circle(16.0);
// printing their diameter
System.out.println("c1,c2,c3,c4 diameters => " + c1.getDiameter() + " " + c2.getDiameter() + " " + c3.getDiameter() + " " + c4.getDiameter());
// printing total count of instances
System.out.println(Circle.getCircleCount()+" circles.");
}
}
Output
c1,c2,c3,c4 diameters => 2.0 8.0 18.0 32.0 4 circles.
// Program is corrected and comments are inline
class Circle {
private double radius;
// this tracks the number of objects created
private static int circleCount = 0;
// constructor
public Circle (double radius) {
circleCount++; // Incrementing by 1 for each time an object is created
this.radius = radius;
}
// getting the diameter of circle
public double getDiameter() {
return radius * 2.0;
}
// getting the total count of instances
public static int getCircleCount() {
return circleCount;
}
}
class CircleTester {
public static void main(String[] args) {
Circle c1, c2, c3, c4;
// creating 4 objects
c1 = new Circle(1.0);
c2 = new Circle(4.0);
c3 = new Circle(9.0);
c4 = new Circle(16.0);
// printing their diameter
System.out.println("c1,c2,c3,c4 diameters => " + c1.getDiameter() + " " + c2.getDiameter() + " " + c3.getDiameter() + " " + c4.getDiameter());
// printing total count of instances
System.out.println(Circle.getCircleCount()+" circles.");
}
}