Chris Pollett>Old Classes>PIC 20, Winter 2000>Hw1>Hw1 Solutions

// Program Name: MeanValue.java
//
// Purpose: This program takes the first command line argument which
//          is assumed to be an integer n and pops up n successive 
//          dialog boxes. The average of these numbers is then
//          presented in a message box.
//
// Known Bugs/
//     Comments: The only exceptional case this program checks for is the
//               case where there is no command line argument.   

import javax.swing.JOptionPane;

public class MeanValue {

        // for this simple program all of the code is in the main method
	public static void main (String args[])
	{
		String inNum;
		int n;
		double sum =0;
		
		if(args.length == 0) //handle case of no cmd line arg
		{
			System.out.println("Please supply the number of"+ 
					" items to be averaged on the command"
					+" line\n");
			System.exit(0);
		}

		n= Integer.parseInt(args[0]);

		for(int i=1; i<=n; i++) // get numbers to avg
		{
		  inNum =JOptionPane.showInputDialog("Enter number"+i+":");
	 	  sum += Double.parseDouble( inNum); // sum as we go
		}

                // print the average
		JOptionPane.showMessageDialog(null,"The average is:"+sum/n
				,"Mean", 			
				JOptionPane.PLAIN_MESSAGE);

 		System.exit(0);
	}

}