<vendor> MVCSoft Inc. would like to announce the immediate availability of the "educational edition" of its EJB 2.0 persistence manager, based on the proposed final draft of the EJB 2.0 specification. You can purchase the persistence manager (including source code) from Flashline at http://www.flashline.com/components/view.jsp?prodid=3703&affiliate id=443755. The cost is only $28.60. The MVCSoft Persistence Manager consists of a deployment-time code processor and an application server-specific runtime component. The code processor takes as input a JAR file conforming to the EJB 2.0 specification, and outputs a JAR file conforming to the EJB 1.1 specification. The generated EJB 1.1- conformant entity beans use the container callbacks for bean- managed persistence and require the presence of the MVCSoft runtime component.This version of the persistence manager provides a runtime for JBoss. The runtime is redistributable along with your application. There is support for EJB 2.0 CMP entity objects, dependent objects, relationships, and the EJB Query Language. Despite being an early release, MVCSoft�s persistence manager provides several important optimizations. It does dirty checking on managed entities, dependent objects, and relationships. This means that if an object or relationship has not been modified, its state is not rewritten to the database. The component developer does not need to provide any code to support this feature (such as an isModified() method.) The persistence manager also loads data on-demand, which means that unnecessary database accesses can be avoided. Also, when dependent objects do need to be loaded for a relationship with a multiplicity greater than one, they are bulk- loaded to avoid multiple database accesses. Finally, finder (and select) queries specified in the new EJB query language are compiled to SQL92 code at deployment time for efficient execution. Additional optimizations are planned for future releases. An equally good reason to purchase the MVCSoft Persistence Manager is the 185 page manual (in PDF format). This manual explains EJB 2.0 persistence in depth, with plenty of sample code. All the basics are covered, and the fine points of using EJB 2.0 entities, dependent objects, relationships, and the new EJB query language are covered as well. Some of the topics include: * The role of the persistence manager * Abstract accessors * The client view * Data aliasing for dependent objects and relationships * Dependent object classes vs. dependent value classes * Granularity and modeling * Rules for EJB 2.0 entities and dependent objects * Referential integrity * Collection-class semantics * Fail-fast iteration * Cartesian joins in EJB QL queries * Range variables vs. path expressions * Single-valued path expressions vs. multi-valued path expressions * The casting operator * Returning dependent value objects from a query * Where clause parameters * Special rules for date literals * Where clause operators I hope you find this product useful. By the way, this makes JBoss one of the first application servers to support the EJB 2.0 specification's proposed container-managed persistence. </vendor> -- -------------------------------------------------------------- To subscribe: [EMAIL PROTECTED] To unsubscribe: [EMAIL PROTECTED] List Help?: [EMAIL PROTECTED]
