Refactor: Remove unnecessary CSV flush operation in loop

[coderabbitai[bot]]

Description

In the class WordLearningEventCsvExportController, there's an inefficient implementation where csvPrinter.flush() is called inside a loop that processes word learning events. Calling flush inside the loop causes unnecessary I/O operations which can impact performance, especially with large datasets.

Current Implementation

for (WordLearningEvent wordLearningEvent : wordLearningEvents) {
  log.info("wordLearningEvent.getId(): " + wordLearningEvent.getId());

  csvPrinter.printRecord(
      wordLearningEvent.getId(),
      wordLearningEvent.getTimestamp().getTimeInMillis(),
      wordLearningEvent.getAndroidId(),
      wordLearningEvent.getPackageName(),
      (wordLearningEvent.getWord() == null) ? null : wordLearningEvent.getWord().getId(),
      wordLearningEvent.getWordText(),
      wordLearningEvent.getLearningEventType(),
      wordLearningEvent.getAdditionalData()
  );
  csvPrinter.flush();
}

Recommended Change

Move the flush() call outside of the loop:

for (WordLearningEvent wordLearningEvent : wordLearningEvents) {
  log.info("wordLearningEvent.getId(): " + wordLearningEvent.getId());

  csvPrinter.printRecord(
      wordLearningEvent.getId(),
      wordLearningEvent.getTimestamp().getTimeInMillis(),
      wordLearningEvent.getAndroidId(),
      wordLearningEvent.getPackageName(),
      (wordLearningEvent.getWord() == null) ? null : wordLearningEvent.getWord().getId(),
      wordLearningEvent.getWordText(),
      wordLearningEvent.getLearningEventType(),
      wordLearningEvent.getAdditionalData()
  );
}
csvPrinter.flush();

File Path

src/main/java/ai/elimu/web/analytics/WordLearningEventCsvExportController.java

Why is this a good first issue?

This is a simple performance optimization that requires minimal code changes but introduces an important concept about efficient I/O operations.

References

• Identified in PR review: https://github.com/elimu-ai/webapp/pull/2114#discussion_r2034634512