[SOLVED] Extracting Tokens Help

[Hunkpapa]

Hello. I'm stuck on something and could use some help...

I'm trying to gather numbers from a user and provide a sum, using a StringTokenizer class to extract the input. I've written the below code which compiles without incident, but crashes when I run it with the following errors:

Exception in thread "main" java.lang.NumberFormatException: For input string: "1,2,3"
at sun.misc.FloatingDecimal.readJavaFormatString(Floa tingDecimal.java:1224)
at java.lang.Double.parseDouble(Double.java:482)
at SumOfNumbers.main(SumOfNumbers.java:24)

Can someone take a look and help me get back on track? Thanks.

import javax.swing.JOptionPane;
import java.util.StringTokenizer;

public class SumOfNumbers
{
	public static void main(String[] args)
	{
		String input;			// User input
		double sum = 0.0;		// Accumulator
		
		// Get a list of numbers.
		input = JOptionPane.showInputDialog("Enter a series of " + 
		                      "numbers separated only by commas: ");
		
		
		// Convert string to numeric data and assign to variable.							 
		sum = Double.parseDouble(input);
		
		// Create a StringTokenizer object.
		StringTokenizer strtok = new StringTokenizer(input, ",");
		
		// Get the numbers and sum them.
		while (strtok.hasMoreTokens())
		{
			input = strtok.nextToken();
			sum += Double.parseDouble(input);
			sum++;
		}
		
		// Display the sum.
		JOptionPane.showMessageDialog(null, "The sum of those " + 
		                              "numbers is " + sum);

		// Exit the applicaton.
		System.exit(0);
	}	
}

[Norm]

I assume that this is the statement at line 24:
sum = Double.parseDouble(input);

What does the API doc say for that method? IF it were smart enough to scanout the separate digits separated by commas,what would it do with all of them? It only returns a single value.
What happens if you take that statement out?
Why do you have that line there if you don't expect a double string?
If you are going to read in a String of digits sep by commas, then you must scan out the digits one by one before converting them to double.

[Hunkpapa]

What happens if you take that statement out?

Umm, it works perfectly. Thanks! Appreciate the help.