interface DurationInterface

interface DurationInterface {
  
  /**
   * Returns the duration.
   *
   * @return \DateInterval|null
   *   A DateInterval object or NULL if there is no duration.
   *
   * @throws \Exception
   */
  public function getDuration();
  
  /**
   * Returns the duration as an ISO 8601 ABNF string.
   *
   * @return string
   *   ABNF-formatted duration.
   *
   * @see https://datatracker.ietf.org/doc/html/rfc3339#appendix-A
   */
  public function getDurationAsIso8601Abnf() : string;
  
  /**
   * Sets the duration.
   *
   * @param \DateInterval $duration
   *   A duration to set.
   */
  public function setDuration(\DateInterval $duration);

}