Question

    String incomingNumbers[ ] = writtenNumber.split("\\-");

The program accepts natural language numbers such as thirty-two or five.
So if five is entered, what lands in my incomingNumbers array?

Answer 1

You get an array of size 1 holding the original value:

Input       Output
-----       ------
thirty-two  {"thirty", "two"}
five        {"five"}

You can see this in action in the following program:

class Test {
    static void checkResult (String input) {
        String [] arr = input.split ("\\-");
        System.out.println ("Input   : '" + input + "'");
        System.out.println ("    Size: " + arr.length);
        for (int i = 0; i < arr.length; i++)
            System.out.println ("    Val : '" + arr[i] + "'");
        System.out.println();
    }

    public static void main(String[] args) {
        checkResult ("thirty-two");
        checkResult ("five");
    }
}

which outputs:

Input   : 'thirty-two'
    Size: 2
    Val : 'thirty'
    Val : 'two'

Input   : 'five'
    Size: 1
    Val : 'five'