Added virtualPosition field to track total bytes written including buffered data.
Updated getPos() to return virtualPosition instead of position + buffer.position().
RESULT:
- getPos() now always returns accurate total (1260 bytes) ✓
- File size metadata is correct (1260 bytes) ✓
- EOF exception STILL PERSISTS ❌
ROOT CAUSE (deeper analysis):
Parquet calls getPos() → gets 1252 → STORES this value
Then writes 8 more bytes (footer metadata)
Then writes footer containing the stored offset (1252)
Result: Footer has stale offsets, even though getPos() is correct
THE FIX DOESN'T WORK because Parquet uses getPos() return value IMMEDIATELY,
not at close time. Virtual position tracking alone can't solve this.
NEXT: Implement flush-on-getPos() to ensure offsets are always accurate.
chrislu