Design and Implementation of Modeling and Validation Facilities for Business Object Documents

As a real or virtual enterprise develops or makes use of more and more software application systems to manage all kinds of resources to conduct its business, the integration of these heterogeneous systems is becoming increasingly important. In a general integration scenario, application systems communicate with one another by sending data in certain data formats such as BODs (Business Object Documents) proposed by the Open Application Group (OAG). In order to ensure that meaningful communications take place, the data must satisfy the constraints of the source and target application systems. In this report, we use the ECAA (Event-Condition-Action-Alternative action) rule paradigm to model the constraints of BODs at build-time and validate these constraints at run-time. The BOD modeling and validation system we developed consists of a set of build-time components and a set of run-time components. At build-time, a graphical user interface tool called XGTOOLS is used to model the " data types " (entities in the OAG terminology. Examples of data types are ITEMLOCATN and ITEMVALUE) of BODs as entity classes that contain attributes, constraints, events, rules and triggers. The modeled entity classes are translated into EXPRESS+ scripts for readability and dictionary interchange files for metadata transfer to other machines. EXPRESS+ is an extension of the EXPRESS modeling language. In addition to the language elements of EXPRESS, EXPRESS+ provides the language constructs for method specification and knowledge specification. Dictionary interchange files containing the metadata of BODs are transferred to a Metadata Manager. The Metadata Manager stores the metadata persistently and provides the application program interfaces (APIs) for accessing and modifying the persistent store. At build-time, the meta information of the entity classes of BODs is translated into Java source code and the corresponding ECAA rules are also translated into Java classes. These rules are enforced at the run-time when an application system generates a new BOD to be sent to other application systems or when an application system receives a BOD from another application system. Since our approach to BOD modeling and validation is not tied to a particular business application, it can be used in any business application integration scenario. Furthermore, our modeling and validation techniques can also be used for modeling and enforcing constraints of objects other than BODs since the object model used in this work is generic.