Modeling of Constraints in Distributed Object-Oriented Environment By CHHANDA RAY DISSERTATION SUBMITTED FOR THE DEGREE OF DOCTOR OF PHILOSOPHY (ENGINEERING)

Object Oriented Data Modeling is gaining popularity because of its elegance in representing real world situations. On the other hand, Integrity constraints traditionally form an essential part of schema definition. In this context, Modeling of constraints in Object Oriented Model has been the focus of attention of many researchers in recent times. Integrating data from many heterogeneous sources require interoperability between the data repositories. Consistency preservation in the context of interoperability is also a key concern in distributed object computing. My work attempts to address these two major issues. This work introduces a novel constraint model for object-oriented data. The constraint model is formalized by expressing it using enhanced Unified Modeling Language (UML) and ODMG's ODL. This enhancement has been done by extending UML metamodel. To increase efficacy of interoperability, the constraint model is also represented by using a standard web based interoperable medium like extensible Markup Language (XML). For efficient manipulation of data into a more manageable model that is native to the programming language, an efficient way of storing XML data with constraint information into Java Object Oriented Programming Language is also introduced. A Wrapper based translator has been developed to accomplish two-way interoperability between XML and Java with constraints. Finally, an XML based unification of data between interoperable object-oriented systems such as Java and C++ has been presented so that efficient queries can be performed in XML environment.