TestBean bean = new TestBean();

        // Test null value (should be valid)
        bean.setCronExpression(null);
        Set<ConstraintViolation<TestBean>> violations = validator.validate(bean);
        assertTrue(violations.isEmpty());

        // Test empty string (should be valid)
        bean.setCronExpression("");
        violations = validator.validate(bean);
        assertTrue(violations.isEmpty());

                "createdTime");
        setupEpg(_epgMap, et -> ((ScheduledJob) et).getCronExpression(),
                (et, vl) -> ((ScheduledJob) et).setCronExpression(DfTypeUtil.toString(vl)), "cronExpression");
        setupEpg(_epgMap, et -> ((ScheduledJob) et).getJobLogging(),
                (et, vl) -> ((ScheduledJob) et).setJobLogging(DfTypeUtil.toBoolean(vl)), "jobLogging");