Only partly. Spark's RDD API which is still used quite heavily requires external serializer. Most of the time you would use Kryo, but it does not fork for objec

Only partly. Spark's RDD API which is still used quite heavily requires external serializer. Most of the time you would use Kryo, but it does not fork for objects larger than 2 GB or sometimes for custom classes that are not explicitly registered as Kryo serializable. In these cases, the changes would break existing code. However, who knows when will Oracle decide to remove the Java serialization API. I expect it will take a few years and the situation will be different on the Spark side then.