how to load data from the database?

Hi everyone
I'm trying to work with engine API to work with my processes, and I don't want to use REST API, so I need to know how can I export my DAO file from the Bonita studio and import it into my java project to work with it?

should I implement the DAO class myself?

Bonita Eclipse Marketplace

Dear All
I want to get knowledge of bonita source code, hence, I want to open Bonita BPM Eclipse Marketplace from "http://marketplace.eclipse.org/content/bonita-bpm#group-details" link. which version of java SDK and eclipse IDE do I need? should I set any configuration in IDE before run it?
I want to get information about Bonita engine and how it handles the tasks that assigned to each user in Process?