I am publishing a NAME_1 message in Json format. The Json has a list of contacts of the customer. For each contact, we have contactId and details.
The contact detail includes contactValue and contactType
The NAME_1 message must contain both the current state of the contact detail and the previous state of the contact detail. Therefore each contact must contain a pair of Contact detail; one contact detail representing current state and one contact detail representing the previous state.

Can you define the corresponding NAME_2 class which includes these details?