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Make ParquetFileReader extensible

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#3,006 11 comments 0 reactions 0 assignees View on GitHub

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Assessment

Difficulty
4/5
Estimated time
3-5 days
Newbie friendliness
42/100
Issue type
Feature
Clarity
Mostly clear
Activity status
Stale
Tech stack
java

Research direction

Start with ParquetFileReader, especially getColumnIndexStore(int blockIndex) and the blocks field, then review the linked KvinParquet reflection usage to identify the required subclass access. Done means ParquetFileReader subclasses can implement the requested cache without reflection, with the chosen protected members or getters documented and covered by appropriate tests.

Written by the indexing model from the issue text.

Description

Type: enhancement
Describe the enhancement requested

I wanted to add a cache for ParquetFileReader.getColumnIndexStore(int blockIndex) and I've noticed that I can't access the required blocks field from a subclass.
To accomplish this I had to fallback to reflection as can be seen here:
https://github.com/linkedfactory/linkedfactory-pod/blob/c67b155e3fbf76082e2b24fd412efae5838badc6/bundles/io.github.linkedfactory.core/src/main/java/io/github/linkedfactory/core/kvin/parquet/KvinParquet.java#L881

I would propose to improve the extensibility of ParquetFileReader by changing certain core members (like blocks) to protected or by exposing them through protected getters.

Component(s)

No response

Dominant language
Java
Stars
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Forks
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Avg merge
6d 16h
Merged PRs (30d)
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