HBase: how to save an object with nested fields like list of lists ?

HBase: how to save an object with nested fields like list of lists ?

let's say i have a class Customer and it has simple fields like firstName,
lastName etc. but also a list of Contacts as field and every Contact
object has a list of emails and a list of telephone numbers. I already
know how the HBase schema could look like with simple String fields like
firstName. But I am not sure how to save the nested fields ( list of
objects, each containing list of other objects or data types). Could any
one assist me with it?
regards