Question

Write a Java console application that prompts the user to enter the radius of a circle, then prints its radius, diameter, circumference, and area. Write a JavaFX GUI application to do the same calculation, and draw the circle.

The Console Output

Enter the radius of the circle: 1.2

The radius is 1.2
The diameter is 2.4
The circumference is 7.5398223686155035
The area is 4.523893421169302

• Write and document your program per class coding conventions.
• Add an instance variable double radius. Generate its get/set methods.
• Manually type the methods getDiameter(), getCircumference(), and getArea(). To calculate the circumference and area, use 3.14159 or the Java defined constant Math.PI
• In main method, create a new instance of Assign3: Assign3 circle = new Assign3();
• Create an instance of Scanner. Call print() to prompt the user to enter the radius. Call input.nextDouble() to get the user input. Call circle.setRadius() to set the radius.
• Then call println() 4 times, each with the value of getRadius, getDiameter, getCircumference, getArea, respectively.

• Use:
  setRadius(radius);              
  String results = "Radius is " + getRadius() + ...;
  circleLabel.setText(results);

Answer 1

 |import javax.swing.JOptionPane;
2 |
3 |public class CirleAreaGUI {
4 |  public static void main(String[] args) { 
5 |    double radius, area;
6 |
7 |    int dialogType = JOptionPane.PLAIN_MESSAGE;
8 |    String input = JOptionPane.showInputDialog(null, 
9 |          "Enter radius ", "Circle Area Input", 
10|          dialogType);
11|    radius = Double.parseDouble(input);
12|    area = Math.PI * Math.pow(radius, 2);
13|    String message = "Area of Circle: " + area;
14|    String title = "Circle Area Output";
15|    JOptionPane.showMessageDialog(null, message, 
16|          title, dialogType);
17|  }
18|}