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Why no bulk Arrow→Parquet write API in Java? How to avoid row-by-row RecordConsumer + optimize?

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Assessment

Difficulty
5/5
Estimated time
Over a week
Newbie friendliness
25/100
Issue type
Feature
Clarity
Needs clarification
Activity status
Stale
Tech stack
java
Domain
data-engineering

Research direction

Start by reviewing the Java write paths named in the issue, especially RecordConsumer, internal column writers, and VectorSchemaRoot, then compare them with the bulk APIs described for C++, C#, and Python. Done means documenting whether a supported bulk Java path exists, explaining the current limitation or roadmap, and identifying the recommended optimization route without JNI.

Written by the indexing model from the issue text.

Description

Describe the usage question you have. Please include as many useful details as possible.

I have ~ 20KB objects that I need to write to Parquet efficiently from Java.
In C++, C#, and Python there's a direct/bulk Arrow-Parquet write (e.g. WriteTable / write_table) that avoids row-by-row iteration, but in Java I only see row-by-row paths via RecordConsumer or internal/unstable column writers.
Questions:

  1. Is there a supported bulk/columnar Arrow-Parquet write API in Java (e.g, VectorSchemaRoot
    → Parquet) that avoids row-by-row calls?
  2. If not, why is Java limited to row-by-row writes today? Any roadmap for feature parity with C++/Python/C#?
  3. For now, what's the recommended optimization path to write 20KB objects at high throughput from Java (without JNI), or is JNI/Dataset the recommended route?
  4. Any best practices (batch sizing, encodings, writer settings) to mitigate the row-by-row overhead?

Thanks

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Dominant language
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