Method minus

base/src/main/java/net/time4j/PlainTime.java:1436–1443

(
        long amount,
        ClockUnit unit
    )

     * @since   4.19
     */
    public PlainTime minus(
        long amount,
        ClockUnit unit
    ) {

        return this.plus(Math.negateExact(amount), unit);

    }

    /**
     * <p>Rolls this time by the given duration (as amount and unit) and