NumberHelper { public static boolean isNumeric(String str) { return numericRegex.matcher(str).matches(); }  static boolean isNumeric(String str); static List<NumberToken> tokenize(String str);  }
@Test public void isNumeric() { assertTrue(NumberHelper.isNumeric("1")); assertTrue(NumberHelper.isNumeric("935")); assertTrue(NumberHelper.isNumeric("a13")); assertTrue(NumberHelper.isNumeric("7B")); assertTrue(NumberHelper.isNumeric("as782u")); assertTrue(NumberHelper.isNumeric("1-2")); assertTrue(NumberHelper.isNumeric("42-0815,47&11")); assertTrue(NumberHelper.isNumeric("42 - 0815 , 47 & 11")); assertTrue(NumberHelper.isNumeric("42a - tt0815 , ll47uu &o11")); assertFalse(NumberHelper.isNumeric("a")); assertFalse(NumberHelper.isNumeric("a-z")); assertFalse(NumberHelper.isNumeric("5-a")); }