/**
  * Rejects the given invitation with the specified reason.
  *
  * @param whiteboardOpSet the operation set to use for rejecting the invitation
  * @param invitation the invitation to reject
  * @param reason the reason for the rejection
  */
 public void rejectInvitation(
     OperationSetWhiteboarding whiteboardOpSet, WhiteboardInvitation invitation, String reason) {
   whiteboardOpSet.rejectInvitation(invitation, reason);
 }