Simple test case
//+
RomanNumberFormat nf = new RomanNumberFormat();
System.out.println("Test of " + nf);
try {
System.out.println("0->" + nf.format(0));
System.out.println("Failed to object to zero");
} catch (NumberFormatException ex) {
System.out.println("Correctly rejected zero");
}
System.out.println("42->" + nf.format(42));
System.out.println("678->" + nf.format(678));
System.out.println("1999->" + nf.format(1999));
System.out.println("2000->" + nf.format(2000)); // Y2K anyone?
System.out.println("2001->" + nf.format(2001)); // Y2K anyone?
System.out.println("3999->" + nf.format(3999));
System.out.println("4000->" + nf.format(4000)); // expect Exception
//-
// parsing not implemented.
System.out.println("XIV->" + nf.parseObject("XIV", null));