Computer Science 202
Introduction to Programming

Fall 2012, The College of Saint Rose

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CircleAreas BlueJ Project

Click here to download a BlueJ project for CircleAreas.

CircleAreas Source Code

The Java source code for CircleAreas is below. Click on a file name to download it.

CircleAreas.java

/*
 * Example CircleAreas: a program that reads in a series of numbers,
 * ending in a negative or 0 value, and prints the results to a given file.
 *
 * Jim Teresco, The College of Saint Rose, CSC 202, Fall 2012
 *
 * $Id: CircleAreas.java 1962 2012-10-29 22:11:21Z terescoj $
 */

import java.io.File;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.Scanner;

public class CircleAreas {

    public static void main(String[] args) throws IOException {
        
        // first, a Scanner to be used to read in a file name
        // and the series of numbers from the keyboard.
        Scanner keyboard = new Scanner(System.in);
        
        // next, we read the file name
        System.out.print("Enter the file name to use to store results: ");
        String fileName = keyboard.next();
        
        // now we are ready to open our file for writing
        PrintWriter outFile = new PrintWriter(new File(fileName));
        
        // next, we will loop until we get a 0
        double radius;
        do {
            System.out.print("Enter the radius of the next circle: ");
            radius = keyboard.nextDouble();
            
            if (radius > 0.0) {
                outFile.println(radius + " " + (Math.PI * radius * radius));
            }
        } while (radius > 0.0);
        
        outFile.close();
    }
}