Exception in thread "main" java.util.NoSuchElementException

[vileoxidation]

I am relatively new to Java, and am writing my programs in Eclipse. I am having somewhat of a strange issue, because my code is compiling fine in Eclipse, but when I submit it (its for a class, and we are using online submission that compiles and runs sample data when you submit) I get an exception. I have no idea what the error means, but here is the entire text of it:


Exception in thread "main" java.util.NoSuchElementException
at java.util.Scanner.throwFor(Scanner.java:838)
at java.util.Scanner.next(Scanner.java:1461)
at java.util.Scanner.nextDouble(Scanner.java:2387)
at Assignment2.main(Assignment2.java:71)


Can anyone tell me what could be going on here? Any help would be much appreciated! My source code is below.

import java.util.*;
import java.text.*;

/*
*******************************************************
DESCRIPTION: This is a program that takes the distance of 
three javelin throws that were entered by the user (in meters),
converts them to yards, feet, inches, and centimeters, and displays the output. 
*******************************************************
*/

public class Assignment2 
{
	  public static void main (String[] args)
	   {
		  // Variable declarations
		  final double M_TO_Y = 1.0936;
		  final double M_TO_C = 100;
		  final double M_TO_F = 3.28084;
		  final double M_TO_I = 39.370;
		  // double distance1;
		  //double distance2; 
		  //double distance3;
		  
		  // Set up for the scanners
		  Scanner competitor = new Scanner(System.in);
		  Scanner user = new Scanner(System.in);
		  Scanner dist1 = new Scanner(System.in);
		  Scanner dist2 = new Scanner(System.in);
		  Scanner dist3 = new Scanner(System.in);
		  
		  // Prompt for competitor's name
		  System.out.print("Enter the competitor's name: ");		  
		  String cName = competitor.nextLine();
		  
		  // Heading for throws
		  System.out.println("\n\t\tOlympic Javelin Throws");
		  
		  // Prompts for the three distances
		  System.out.println("\n\tEnter the distances, in meters, for " 
				  + cName + ":");
		  System.out.print("\nPlease enter the distance for throw 1: ");
		  	double distance1 = dist1.nextDouble();
		  System.out.print("Please enter the distance for throw 2: ");
		  	double distance2 = dist2.nextDouble();
		  System.out.print("Please enter the distance for throw 3: ");
		  	double distance3 = dist3.nextDouble();
				  
		  // Heading for conversion chart
		  System.out.println("\n\tyards\t\tfeet\t\tinches\t\tcm");
		  
		  // Decimal formatting set-up
		  DecimalFormat fmt = new DecimalFormat ("0.##");
		  
		  // Conversions for distance1
		  System.out.print("\t" + fmt.format(distance1 * M_TO_Y));
		  System.out.print("\t\t" + fmt.format(distance1 * M_TO_F));
		  System.out.print("\t\t" + fmt.format(distance1 * M_TO_I));
		  System.out.println("\t\t" + fmt.format(distance1 * M_TO_C));
		  
		  // Conversions for distance2
		  System.out.print("\t" + fmt.format(distance2 * M_TO_Y));
		  System.out.print("\t\t" + fmt.format(distance2 * M_TO_F));
		  System.out.print("\t\t" + fmt.format(distance2 * M_TO_I));
		  System.out.println("\t\t" + fmt.format(distance2 * M_TO_C));
		 
		  // Conversions for distance3
		  System.out.print("\t" + fmt.format(distance3 * M_TO_Y));
		  System.out.print("\t\t" + fmt.format(distance3 * M_TO_F));
		  System.out.print("\t\t" + fmt.format(distance3 * M_TO_I));
		  System.out.println("\t\t" + fmt.format(distance3 * M_TO_C));	
		  
	   } // End of main method
	} // End of Assignment2 class

[Fubarable]

1) Did you read the Scanner API and see when, where, and why it throws this exception?
2) How are you getting the "sample data" into the program? That's key here. Are you sure that System.in will work the same when you compile and run your code via online submission?

[vileoxidation]

Thank you for the reply!

Where is the Scanner API? As I said, I am new to this, so I really don't know what that is. I have seen, in google searches, that it happens because the "input is exhausted," but I don't know what that actually means.

Well, I don't exactly know how the online submission works. I just submit the file, and then the screen in the screenshot below comes up.

[Eranga]

1) Did you read the Scanner API and see when, where, and why it throws this exception?

This is interesting. First of all try to find what that exception exactly means. Basically it indicates that there are no more elements in enumeration. So the best thing is to check the data source.

[Fubarable]

I think that it's time to talk to your teacher; that's what I think

[vileoxidation]

This is interesting. First of all try to find what that exception exactly means. Basically it indicates that there are no more elements in enumeration. So the best thing is to check the data source.

I am trying to understand the error, but all I can pull out (and this is just a guess) is that there is something wrong between how my program is handling the data and the data itself. I think that is also what "the input is exhausted" means, but I don't know how to change the program to work with the data.

Is it a problem with the "nextDouble" term and the input? Should "nextDouble" be something else, or is there something wrong with my scanner, or something entirely different?

I think that it's time to talk to your teacher; that's what I think

Well, that is my next option. I just wanted to try to figure it out first, and understand the exception, especially since I am unsure exactly how much help my teacher will be willing to provide.

Thank you for the help. I will just get in contact with my teacher. :)