| Present JDO technical specification is researched and discussed in this paper. Various kinds of life-cycle states and those mainly transform processes, which base on the introduction of the JDO technical specification's history and architecture, are provided by the article. At present, it has lots of shortcomings that relational database management system stores persistence object and is visited by JDBC and SQL language. Aim at these shortcomings, we discuss the application of storing persistence object through a concrete information system instance. JDO technology can store or query database in transparent way. JDO abandons traditional JDBC visiting database's mode completely, expresses object- oriented better, and maintain the encapsulation and persistence of the object. Therefore JDO can shorten the software development period, improve the developing speed and developing quality.JDO technical specification is not perfect enough to the basic query for the instance assembles presently. We can expand and improve it with the aid of Query class factory of persistence manager, so as to improve its functions, such as query, statistics, and so on. Nowadays, EJB technology is so ripe way in the managerial persistence storage that it can fine settlement instance distribution problem of the information system well. But it can not settle the problem well of the object 's persistence storage. JDO technical specification would remedy this defect. Integration of JDO and EJB was put forward in this paper, which can eliminate the semantic difference between local and remote invocation in EJB technology, enhance entity beans support for object inheritance, settle down the issure that the persistence and query function of EJB must be coded by hand. The problem that EJB technology's persistence and distribution can't be united well was resolved by the integration of JDO and EJB.
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