Hi,

I am just starting out and have what is probably a silly question but
any help would be appreciated.

I am trying to run the first example in the Java In a Nutshell 5th
edition book. Here is the code:

/**
* This program computes the factorial of a number
*/
public class Factorial {                         // Define a class
  public static void main(String[] args) { // The program starts here
     int input = Integer.parseInt(args[0]); // Get the user's input
     double result = factorial(input);        // Compute the factorial
     System.out.println(result);              // Print out the result
  }

  public static double factorial(int x) {    // This method computes
x!
     if (x < 0)                                       // Check for bad
input
        return 0.0;                                 // If bad, return
0
     double fact = 1.0;                         // Begin with an
initial value
     while(x > 1) {                               // Loop until x
equals 1
        fact = fact * x;                          // Multiply by x
each time
        x = x - 1;                                 // And then
decrement by x
     }                                                // Jump back to
start of loop
     return fact;                                  // Return the
result
  }                                                   // factorial()
ends here
}                                                      // The class
ends here

Using the JDK I type "javac Factorial.java" and it seems to compile ok
and creates Factorial.class. However when I try to run that with "java
Factorial 4" I get the error message:
Exception in thread "main" java.lang.NoClassDefFoundError: Factorial.

I am not sure what I have done wrong. The code is exactly as it is in
the book and I even downloaded it from their website and tried it and
the same thing happened. What am I doing wrong?

Thanks,

Alex