The Design Of Data Access Layer Of Network Management System Based On J2EE

Data permanent layer is a difficult issue in the enterprises development. A prompt client sever computer affair is a must in solving an enterprise's data permanence. Among J2EE, there are many different technologies to solve this problem. As a new and simple ORM frame, hibernate can substitute"entity bean". Combine with DAO frame, hibernate can draw out a comparative independent data permanent layer. It emphasizes on achieving the permanence of data, and achieves such a soft coupling between data access logic and data resource. At the same time, hibernate can minish the complexity of the development of projects. It accords with Java's criterion in permanence of relational database. Just start from this point, hibernate can also make the projects more maintainable and expandable.Firstly it elicits two kinds of methods in designing data permanent layer under J2EE: (1) CMP under EJB 2.X frame, (2) Hibernate ORM frame. About (1), it introduces the implement of data permanence using in the network management system based on EJB 2.X. In this segment, it emphasizes on the process of CMP's implement under this frame. About (2), it introduces the technological theory firstly. Aim at all kinds of advantages in using CMP to access data permanence in the big network management system, it puts forward a new frame to subsitute CMP under EJB 2.X, that is the simple Hibernate ORM frame, through this method, it can find out a way to make data permanent layer optimize in the network managemente systerm.