@Override
  public PartitionedRegion getPartitionedRegion() {
    if (!isUsedForPartitionedRegionBucket) {
      throw new IllegalArgumentException();
    }
    return ((Bucket) this).getPartitionedRegion();
  }
A convenience method to get the PartitionedRegion for a Bucket

@return If this is an instance of {@link BucketRegion}, returns the {@link PartitionedRegion}
        otherwise throws an IllegalArgumentException
geode-core/src/main/java/org/apache/geode/internal/cache/LocalRegion.java