Motivation

shuffleWithMask is used by topology-aware read reordering to shuffle contiguous WriteSet entries with the same mask. When the matched range is at the end of the logical WriteSet, the current loop starts from last + 1, which is outside the active range.

Since WriteSet instances are recycled and may retain a larger backing array than their current logical size, accessing size can reuse stale bookie indexes from a previous use.

Changes

• Shuffle only within the matched range [first, last].
• Treat index == size as out of bounds in WriteSetImpl.
• Add coverage for get(size), set(size, ...), and moveAndShift(..., size).

Verifying this change

mvn -pl bookkeeper-server -Dtest=TestRackawareEnsemblePlacementPolicy#testShuffleWithMask,RoundRobinDistributionScheduleTest test -DskipShade -Dspotbugs.skip -Dlicense.skip