public DistributedMember getMemberOwning(Object key) {
    int bucketId = PartitionedRegionHelper.getHashKey(this, null, key, null, null);
    return getNodeForBucketRead(bucketId);
  }
Test Method: Get the DistributedMember identifier for the vm containing a key

@param key the key to look for
@return The ID of the DistributedMember holding the key, or null if there is no current mapping
        for the key
geode-core/src/main/java/org/apache/geode/internal/cache/PartitionedRegion.java