[4.0.1] ArrayIndexOutOfBoundsException

[hrstoyanov]

Environment Details

• EclipseStore Version: 4.0.1
• JDK version: 25.0.2
• OS: MacOS Tahoe

Describe the bug

Eclipse Store 4.0.1 has a bug in AbstractCompositeBitmapIndex.internalHandleChanged() (line 528-537).

Root cause: When updating an entity whose composite-indexed field changes from null → non-null:

1. null produces NULL() sentinel = Object[1]
2. Non-null Instant produces Object[6] (year/month/day/hour/min/sec)
3. ensureSubIndices(newKeys) grows the sub-index array from 1 to 6
4. The loop then calls subIndex.internalHandleChanged(oldKeys, ...) for all 6 sub-indices
5. Sub-indices at positions 1-5 access oldKeys[position] — but oldKeys has length 1 → ArrayIndexOutOfBoundsException

The fix (in Eclipse Store) should guard internalHandleChanged in AbstractCompositeBitmapIndex to skip sub-indices whose position exceeds oldKeys.length, or pad oldKeys to match newKeys.length.

To Reproduce

See the attached reproducer

SubBitmapIndexHashingBugTest.java

[hrstoyanov]

@fh-ms - I attempted to write a PR #624 fix for this