Ejb Architecture-based O / R Mapping Theory And Implementation,

With the development of computer technology and generalization of its application, traditional relation database is more and more uncomfortable for new requirement especially for application development based on Internet, which lead to emergence of a new generation of database system, pure object-oriented database (OODBMS). OODBMS support all the characteristics of objects. Pure object oriented database management system which supports all the characteristics is advanced on concept and technology, but much lagging on the capacity of supporting traditional data type. However, most of consumer applications are based on traditional data type, in order to be compatible and protect their previous investment and application, generalization of pure object oriented data base system have to be delayed.On the other hand, with the continuously developing of saftware technology ,OOA,OOD and OOP become popular.More and more Application hava developed using object-technology.But the developer are favored with the relation database system for a long time. The relation database system will still used .The operation oriened object hava behind in the development of applition oriened object. Searching the method of accessing object in relation environment are of great urgency now. This is O/R Mapping(Object Relation Mapping) technology. This technology provide guaeantee for the development of applition system oeiened object techology. Also supply the necessary prepare for the popular of OODBMS.First the necessity of O/R Mapping theory generation, development, application and research category have been analyzed in line with the development of relation database and object technology, and its relevant technology has been summarized briefly, which including relation theory , object theory and XML technology.Then, O/R Mapping solution is highlighted and a generalized mapping mode from object to relation table, including mapping object, constraint condition, mode/pattern language. Based on this pattern, the basic strategy from all kinds of appearance to relation table has been analyzed in detail.In the end, the basic mode based on EJB architecture development has been analyzed, the deficiency of current O/R Mapping problem has been explained and a novel development mode is proposed. The development based on EJB architecture gets much easier with the application of self-independent-development PERO system. At last PERO system architecture, design and function has been highlighted.Above all, the implementation method of O/R Mapping has been exploited in theory in this thesis, a generalized mode for the solution of O/R Mapping, and a development system for EJB architecture exploitation has been implemented.