public static boolean isValid(@Nullable final String dayOpeningHours) {
        if (dayOpeningHours == null) {
            return true;
        }
        final int p = dayOpeningHours.indexOf(' ');
        if (p < 0) {
            return false;
        }
        final String dayOfTheWeekStr = dayOpeningHours.substring(0, p);
        final String hourRangesStr = dayOpeningHours.substring(p + 1);
        return DayOfTheWeek.isValid(dayOfTheWeekStr) && HourRanges.isValid(hourRangesStr);
    }
public static boolean isValid ( @ Nullable final String dayOpeningHours ) { if ( dayOpeningHours == null ) { return true ; } final int p = dayOpeningHours . indexOf ( ' ' ) ; if ( p < 0 ) { return false ; } final String dayOfTheWeekStr = dayOpeningHours . substring ( 0 , p ) ; final String hourRangesStr = dayOpeningHours . substring ( p + 1 ) ; return DayOfTheWeek . isValid ( dayOfTheWeekStr ) && HourRanges . isValid ( hourRangesStr ) ; }
Verifies if the string can be converted into an instance of this class.

@param dayOpeningHours
String to test.

@return {@literal true} if the string is valid, else {@literal false}.