The XQuare components: integrating XQuery and J2EE technologies

Odonata's offer is based on two data integration components that allow heterogeneous enterprise information to be accessed, transformed, stored, queried, integrated and published as a single view using the XML format. The XQuare components perfectly fit with the standard XML exchange, processing and publishing tools, which are now integrated in J2EE platforms.

The XQuare components extend a J2EE application server into an integration and exchange server by adding to it XML data import/export and heterogeneous data sources federation functionalities:

• XQuare Bridge expands existing relational database functionalities with advanced XML import/export capabilities. It supports flexible extraction and publishing of relational data into any target XML format, using the XQuery language. Using a powerful mapping language, it can also perform efficient insertion of structured XML data into existing relational tables, while taking into account the database integrity constraints and transforming the implicit relations appearing in the XML document into explicit ones in the database.
• XQuare Fusion is a powerful information integration engine for querying in real-time multiple, heterogeneous and distributed data sources. Using XML-based data sources federation, it presents to applications a single, uniform XML view of all business information, which can then be queried with XQuery to produce XML documents. Accessible data sources include relational databases (through the XQuare Bridge component), XML documents, Web Services and potentially much more, including XQuery-enabled data sources and applications accessible through JCA connectors.

Both components are distributed as JAR files, easily embeddable in J2EE application servers or in more basic client-server applications. They use the same XML/DBC Java API for acessing and querying data sources. XML/DBC is directly derived from the standard JDBC API for accessing relational databases, but uses XQuery instead of SQL as query language, and the JAXP APIs for processing XML documents and query results. XML documents and query results validation and typing is performed with a fully compliant XML Schema processor.

The XQuare components are distributed as open source software using the GNU Lesser General Public license (LGPL), and can be easily integrated with other open source software, such as the JOnAS application server, the Tomcat servlet container or the Apache XML processing tools. The components can be downloaded from the XQuare community site.

Thanks to their functionalities and integrability, the XQuare components increase the developers productivity and overall application maintenability for applications such as:

• Real-time publishing of heterogeneous data stored in several data sources.
• Real-time data mining for business intelligence.
• Information exchange automation within the enterprise and with its partners.
• Intranet and Extranet portals.