Notification (@NotNull NotificationGroup notificationGroup, @NonNls @Nullable String displayId, @NotificationTitle @NotNull String title, @NotificationContent @NotNull String message, @NotNull NotificationType type, @Nullable NotificationListener listener) { // title can be empty; message can't be neither null, nor empty if (StringUtil.isEmptyOrSpaces(message)) { message = title; title = ""; } // if both title and message were empty, then it is a problem in the calling code => Notifications engine assertion will notify. Notification notification = notificationGroup.createNotification(title, message, type); if (displayId != null && !displayId.isEmpty()) notification.setDisplayId(displayId); if (listener != null) notification.setListener(listener); return notification; }