Research And Design Of Integrate Hibernate And EJB FrameWork Persistent Component And Component Migration

With the development of taking Web as the central application procedure, it is very key that the information technology departments fast construct large-scale enterprise distributed applications,however,EJB precisely appears under this back-ground.But EJB difficulty with studied and used already becomes the fatal danger which effects EJB or J2EE to grow strong, the primary cause is that Entity Bean with responsibility for persistent objects technology mapping complexity ,not only don't supports the SQL level inquiry but also the different manufacturers provide different middlewares and so on flaws.Many outstanding ORM middlewares arise at the historic moment, for example: Hibernate, ibatis,JDO,TopLink,Castor and so on.Now, the object-oriented software design has become the mainstream of the software development technology. ORM takes as the important technology in the object-oriented design, whose essence is mapping tool between object territory mode and relational database mode. Hibernate with the characteristic of the open source and mapping flexibility becomes the first choice of all ORM middlewares.It not only provides ORM mapping service, but also provides object-oriented Query Language HQL ,dynamic query, data caching and can nicer integrate with various Web servers and application servers.The component structure of statically configured distribution prevents web application from being adaptive to the changing environmental at runtime.In order to enhance the characteristic which entrusts with heavy responsibility the nature, the large-scale users visit concurrently, the framework should provide the capability which the components migrate at runtime to adapt environmental variation to enhance the system overall performance and the throughput, the flexibility and the extendibility.This thesis researches the key point, which is the J2EE architecture persistent and the components dynamic migration technology.First the J2EE architecture is detailed discussed next thorough researches EJB architecture including EJB classification, respective characteristic and life cycle.Especially detailed researches Entity Bean persistent principle as well as the primary key generation strategies.The following closely researches the Hibernate architecture and persistent principle at the same time, compared with several kinds of commonly used ORM mapping tool,and has solved the asynchronous advancement inquiry cache function in this foundation.In view of the Entity Bean existence shortcoming, Hibernate takes place of Entity Bean and two frames integrates together, which provides one kind of model for the development large-scale distributional application.The frame of integrated Hibernate and EJB provides the dynamic migration ability to realize load equalization, good traffic capacity and server redistribution ability, first compares the current mainstream components development technology, next in detail discusses the necessity which the components migrate and designs the model to aim at one kind of components migrationg, in view of the key question which in the migration process involves, thus designes one algorithm to realize the components dynamic migration, finally, develops a distributional application system under the integrated frame.