jjeonghak

// The optimal equilibrium between real-time responsiveness and server load
private static PERIOD_MS = 500;
setInterval(() => {
  for (const [userId, connection] of this.activeConnections) {
    this.sendPendingEvents(userId, connection);
  }
}, BroadcastService.PERIOD_MS);

jjeonghak

// Core versioning logic (simplified)
for (const connection of activeConnections) {
  const missed = eventQueue.filter(
    e => e.userId !== connection.userId && connection.version < e.event.version
  );
if (missed.length > 0) {
    connection.respond(missed.map(e => e.event));
  }
}

jjeonghak

public void validateArchive(...) {
    // Because the engine is dynamic, we must manually verify data integrity.
    // Example: Check if the provided ChoiceId actually belongs to the QuestionId.
    boolean isValid = questionDetailsList.stream()
            .anyMatch(q -> q.getChoices().stream()
            .anyMatch(c -> c.getId().equals(targetChoiceId)));

    if (!isValid) {
        throw new InvalidRequestArgumentException("Inconsistent answer data detected.");
    }

jjeonghak

private List<SurveyorActivity> createPhotoActivities(...) {
    // Using RxJava's zip operator to synchronize S3 uploads with database persistence.
    // The activity record is only created if both the upload and data mapping succeed.
    return Observable.zip(
            Observable.fromIterable(photos),      // Binary files
            Observable.fromIterable(photoAnswers), // Answer metadata
            (file, answer) -> {
                AmazonS3Carrier.BucketObjectDetails s3Details = 
                    amazonS3Service.putImageToBucket(answer.getQuestionId(), file);
                

jjeonghak

// We fetch questions, choices, and previous answers in one optimized query.
public List<QuestionDetails> fetchSurveySchema(Long gameId) {
    List<QuestionData> records = queryFactory
        .select(Projections.constructor(QuestionData.class,
            QQuestion.question.id,
            QQuestion.question.content,
            QChoice.choice.id,
            QChoice.choice.content))
        .from(QQuestionMapping.questionMapping)
        .join(QQuestion.question).on(QQuestionMapping.questionId.eq(QQuestion.question.id))