Method move

base/src/main/java/net/time4j/engine/StdOperator.java:425–440

(
        T entity,
        boolean forward
    )

    }

    private T move(
        T entity,
        boolean forward
    ) {

        if (entity instanceof TimePoint) {
            TimePoint<?, ?> tp = TimePoint.class.cast(entity);
            Object answer = add(tp, this.element, forward);
            return entity.getChronology().getChronoType().cast(answer);
        } else {
            throw new ChronoException(
                "Base units not supported by: "
                    + entity.getChronology().getChronoType());
        }

    }

    // wildcard capture
    private static <U, T extends TimePoint<U, T>> T add(