public List<String> getInvalidityInfo() { // id is allowed to be null when the student is not registered Assumption.assertTrue(team != null); Assumption.assertTrue(comments != null); FieldValidator validator = new FieldValidator(); List<String> errors = new ArrayList<String>(); String error; if (isRegistered()) { error = validator.getInvalidityInfo(FieldType.GOOGLE_ID, googleId); if (!error.isEmpty()) { errors.add(error); } } error = validator.getInvalidityInfo(FieldType.COURSE_ID, course); if (!error.isEmpty()) { errors.add(error); } error = validator.getInvalidityInfo(FieldType.EMAIL, email); if (!error.isEmpty()) { errors.add(error); } error = validator.getInvalidityInfo(FieldType.TEAM_NAME, team); if (!error.isEmpty()) { errors.add(error); } error = validator.getInvalidityInfo(FieldType.SECTION_NAME, section); if (!error.isEmpty()) { errors.add(error); } error = validator.getInvalidityInfo(FieldType.STUDENT_ROLE_COMMENTS, comments); if (!error.isEmpty()) { errors.add(error); } error = validator.getInvalidityInfo(FieldType.PERSON_NAME, name); if (!error.isEmpty()) { errors.add(error); } return errors; }