Well your class diagram fro Data would be something like company_id company_name str(30), company_email_address1 str(40), company_n_contract int
and you methods would be something like
get_company_name
set_company_name
..............
getters and setters for each entity
.............
The Pascal code might depend a bit on you flavour of Pascal (e.g. Delphi) but shoudl flow really easily from the UML