C. Data object model variants

Our generator tool supports generally two different data object models, one is locally developed data model based on named datasets and intended to give support for extension of older applications developed in .NET framework 1.0 or 1.1, while another option is using of model based on the Entity Framework.

Our data model is based on the standard Microsoft’s data adapter mechanism. For each table, we create adequate DataAdatper object with automatically generated SQL commands (select, insert, update, delete). Further, classes representing data tables are created, where each column has been represented in the class with bidirectional property.

Base class in this generation process is a class Table from Figure 5. It contains reference to data adapter, as well as implementation of basic object related methods – add, update, delete, select. This class is base class for two classes – SqlTable and OracleTable. Generated classes will be subclasses of two mentioned classes, depending whether support for Sql Server or Oracle has been chosen.

In both cases, result of generation is a single library (dll) enabling communication with the database and which can be included in other projects. Also, in both cases, resulting library has same façade interface so they can be easily replaced in the containing projects.

For generating Entity Framework based library we used EdmGen2 application based on ConceptualEdmGen library.

Figure 9 Factory – pattern structure used to control the process of class generation