public InternalDistributedMember getBucketPrimary(int bucketId) {
    return getRegionAdvisor().getPrimaryMemberForBucket(bucketId);
  }
Return the primary for the local bucket. Returns null if no primary can be found within
{@link DistributionConfig#getMemberTimeout}.

@return the primary bucket member
geode-core/src/main/java/org/apache/geode/internal/cache/PartitionedRegion.java