Developing a Web Service for Distributed Persistent Objects in the Context of an XML Database Programming Language

The development of data centric applications should be performed in a high-level and transparent way. In particular, aspects concerning the persistency and distribution of business objects should not influence or restrict the application design. Furthermore applications should be platform independent and should be able to exchange data independently of their programming language origin. There are several approaches for an architecture for distributed objects. One example is CORBA. JDO and EJB allow specifications for distributed persistent objects offering transparent persistency up to a certain degree. Nevertheless, the programmer is still forced to write explicit code for making objects persistent or for connecting to distributed objects. In contrast to existing approaches, the XOBEDBPL project develops a database programming language with transparency with respect to types, and persistency and distribution with respect to objects. Application development is performed on a high-level business object level only. A web service for realizing distributed persistency and data exchange is internal and completely integrated in the XOBEDBPL runtime environment. Although the XOBEDBPL language is an extension of the Java programming language, the introduced concepts could be easily transferred to other object-oriented programming languages.