Design of Database Middleware in NATS

In Networked Automatic Testing System(NATS),this paper presents a database model which combines DataBase Management System(DBMS) with file system.Relying on this model,it designs and implements a database middleware of NATS based on Java technology.The middleware provides a unified Application Programming Interface(API) for user,provides a general CRUD function and data access service of,enhances scalability and reusability and reduces the burden of maintenance and upgrade for NATS.