Sonja Ristić

An approach to the specification of user interface templates for business applications

Through a number of research projects we propose a form-driven approach to business application generation. Our IIS*Studio development environment (IIS*Studio DE, current version 7.1) is aimed to support the form-driven approach and provides the information system (IS) design and generating executable business application prototypes. An executable business application specification, generated by means of IIS*Studio, may be visually interpreted in different ways. In the paper we present the extension of the IIS*Studio repository containing the common model of user interface (UI). The IIS*UIModeler is an integrated part of the IIS*Studio development environment, aimed at modelling UI templates. Applying it, a designer specifies UI templates. UI template specification contains attribute values that describe common UI characteristics, such as: screen size, main application window position, background/foreground colour, etc. UI template specifications are independent from any specific IS project specification, generated by means of IIS*Studio tool. The same UI template may be used for the business application prototype generation of different ISs. Also, the same IS project specification may be visually interpreted in different ways by means of different UI templates. The specification of a UI template may be seen as a fully platform independent UI model. Besides the detail description of UI template common model, we illustrate the main features of the IIS* UIModeler tool.

A model-driven approach to data structure conceptualization

Reengineering of an existing information system can be carried out: to improve its maintainability, to migrate to a new technology, to improve quality or to prepare for functional enhancement. An important phase of a data-oriented software system reengineering is a database reengineering process and, in particular, its subprocess - a database reverse engineering process. The reverse engineering process contains two main phases: data structure extraction and data structure conceptualization. In the paper we present a blueprint of a model-driven approach to database reengineering process that is one of the results of our research project on model-driven intelligent systems for software system development, maintenance and evolution. Within that process hereinafter we focus on the data structure conceptualization process and propose a model-driven approach to data structure conceptualization. Proposed process is based on model-to-model transformations implemented by means of Atlas Transformation Language.

Extended Entity-Relationship approach in a Multi-Paradigm Information System Modeling Tool

In this paper we present a Multi-Paradigm Information System Modeling Tool (MIST) that supports Extended Entity-Relationship (EER) approach to database design. MIST components currently provide a formal specification of EER database schema specification and its transformation into the relational data model, or the class model. Also, MIST allows generation of Structured Query Language (SQL) code for database creation and procedural code for implementing database constraints. In addition, Java code that stores and processes data from the database, may be generated from the class model.

Database reverse engineering based on meta-models

Reengineering is one of the key concepts in software maintenance and evolution. It generally includes some form of reverse engineering followed by some form of forward engineering or restructuring. In the paper we focus on database reverse engineering. Model-driven software engineering promotes the idea of abstracting implementation details by focusing on: models as first class entities and automated generation of models or code from other models. In the approach meta-models are used to define the modeling languages. A database reverse engineering process can benefit of integrating meta-modeling and meta-models in the process. The plethora of models related to databases points out to the need and importance of model-to-model transformations between these models at different abstraction levels. These transformations are based on meta-models that are conformed by the source and target models of the transformations. A database reverse engineering process can be performed through a chain of model-to-model transformations based on a set of meta-models. In the paper we discuss the importance of meta-modeling in the context of database reverse engineering and present a case study illustrating an approach to database reverse engineering.

Extended Tuple Constraint Type in Relational and XML Data Model: Definition and Enforcement

A database management system (DBMS) should provide capabilities for defining and enforcing certain integrity constraints that must hold for the data recorded in the database. These constraints are derived from the semantics of the data and from the rules of the system under study (SuS) that database represents. Every DBMS is based on a data model that provides the means to achieve data abstraction and to express database schema. Each data model has a specific set of integrity constraints types. Some of constraint types are common for several data models and some of them are typical for a data model. Beyond well-known constraint types there are more complex ones that are difficult to express and enforce within the data model. In this paper we deal with the extended tuple constraint (ETC) type. It is the extension of tuple constraint that is one of constraint types of relational data model. In this paper we explain the usage of extended tuple constraint in relational data model and its implementation in relational DBMSs. XML data model does not recognize ETC type. We specify the extended tuple constraint in XML data model and propose two techniques for implementation of ETC in XML DBMSs. Each of them depends on the characteristics of a selected XML DBMS. We use XQuery functions in eXist DBMS, and triggers in Sedna DBMS.

Consolidation of database check constraints

Independent modeling of various modules of an information system (IS), and consequently database subschemas, may result in formal or semantic conflicts between the modules being modeled. Such conflicts may cause collisions between the integrated database schema of a whole IS and the modeled subschemas. In our previous work, we have proposed criteria and algorithms for identifying and resolving such conflicts so as to provide a consolidation of database subschemas with the integrated database schema with respect to various database concepts, such as domains, relation schemes, primary key constraints and referential integrity constraints. In this paper, we propose a new approach and algorithms for identifying conflicts and testing consolidation of subschemas with the integrated database schema against check constraints. The proposed approach is based on satisfiability modulo theory (SMT) solvers. Hereby, we propose the integration of SMT solvers into our MDSD tool, aimed at supporting a database schema integration process.

A model-to-model transformation of a generic relational database schema into a form type data model

An important phase of a data-oriented software system reengineering is a database reengineering process and, in particular, its subprocess - a database reverse engineering process. In this paper we present one of the model-to-model transformations from a chain of transformations aimed at transformation of a generic relational database schema into a form type data model. The transformation is a step of the data structure conceptualization phase of a model-driven database reverse engineering process that is implemented in IIS*Studio development environment.

A tool for modeling form type check constraints

IIS*Case is a software tool that provides information system modeling and generating executable application prototypes. At the level of platform independent model specifications, IIS*Case provides conceptual modeling of database schemas that include specifications of various database constraints, such as domain, not null key and unique constraints, as well as various kinds of inclusion dependencies. In the paper, we present new concepts and a tool embedded into IIS*Case, that are aimed to support specification of check constraints. We present a domain specific language for specifying check constraints and a tool that enables visually oriented design and parsing check constraints.