if (room == null) { throw new DomainException("error.summary.no.room"); }
    private void checkParameters(MultiLanguageString title, MultiLanguageString summaryText,	    Boolean isExtraLesson, Professorship professorship, String teacherName, Teacher teacher,	    Shift shift, Lesson lesson, YearMonthDay date, OldRoom room, Partial hour) {	if (title == null || title.getAllContents().isEmpty()) {	    throw new DomainException("error.summary.no.title");	}	if (summaryText == null || summaryText.getAllContents().isEmpty()) {	    throw new DomainException("error.summary.no.summaryText");	}	if (shift == null) {	    throw new DomainException("error.summary.no.shift");	}	if (date == null) {	    throw new DomainException("error.summary.no.date");	}	if (professorship == null && StringUtils.isEmpty(teacherName) && teacher == null) {	    throw new DomainException("error.summary.no.teacher");	}	if (isExtraLesson) {	    if (room == null) {		throw new DomainException("error.summary.no.room");	    }	    if (hour == null) {		throw new DomainException("error.summary.no.hour");	    }	} else {	    if (lesson == null) {		throw new DomainException("error.summary.no.lesson");	    }	}    }