private <T> void assertMaxOneItemInArray(final SoftAssertions softAssertions,
                                             final String className,
                                             final String name,
                                             final T[] arr) {
        softAssertions.assertThat(arr.length)
                .withFailMessage(className +
                        " - " +
                        name +
                        " is only allowed to have zero or one items.")
                .isLessThanOrEqualTo(1);
    }
This ia more of a QA to ensure all the annotations are set correctly for the functions
stroom-query/stroom-query-language/src/test/java/stroom/query/language/functions/TestFunctionFactory.java