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" Why Object Teams? Team spirit for your objects Building complex systems from isolated objects often yields poor structure which readily decays during system evolution. Objects should team-up in order to co-operate and jointly deliver complex behaviors. Objects play specific roles within a given Team. Context based dispatch Role instances are attached as specializers to existing objects. Object behavior is controlled by the currently active context that determines which roles are active at a given point in time. Contexts are reified into team instances, which may further be used to mediate between roles and maintain state of the collaboration. Modules larger than classes On the road to re-use of modules larger than classes two approaches compete: frameworks and components. For many applications white box frameworks are too fragile and black box components to rigid. Object Teams provide a middle road which balances encapsulation and adaptability. "

Data, Context and Interaction (DCI) is a paradigm used in computer software to program systems of communicating objects. Its goals are: To improve the readability of object-oriented code by giving system behavior first-class status; To cleanly separate code for rapidly changing system behavior (what the system does) from code for slowly changing domain knowledge (what the system is), instead of combining both in one class interface; To help software developers reason about system-level state and behavior instead of only object state and behavior; To support an object style of thinking that is close to peoples' mental models, rather than the class style of thinking that overshadowed object thinking early in the history of object-oriented programming languages. The paradigm separates the domain model (Data) from Use cases (Context) and Roles that objects play (Interaction). DCI is complementary to Model-view-controller (MVC). MVC as a pattern language is still used to separate the data and its processing from presentation. DCI was invented by Trygve Reenskaug, also the inventor of MVC. The current formulation of DCI is mostly the work of Reenskaug and James O. Coplien.

Caching is the most important performance optimization technique. There are many things that can be cached in persistence, objects, data, database connections, database statements, query results, meta-data, relationships, to name a few. Caching in object persistence normally refers to the caching of objects or their data. Caching also influences object identity, that is that if you read an object, then read the same object again you should get the identical object back (same reference). JPA 1.0 does not define a shared object cache, JPA providers can support a shared object cache or not, however most do. Caching in JPA is required with-in a transaction or within an extended persistence context to preserve object identity, but JPA does not require that caching be supported across transactions or persistence contexts. JPA 2.0 defines the concept of a shared cache. The @Cacheable annotation or cacheable XML attribute can be used to enable or disable caching on a class.

The Fornax-Platform is a development platform for tools related to the Model-Driven-Software-Development - MDSD. In this context tools are cartridges, transforms, ready-to-use generators or simple enhancements to make it easier to work in a MDSD environment. Another approach is to provide Howto's and tutorials that simplify the undestanding of MDSD. The Fornax-Platform provides infrastructure and tools to simplify the management and the development of such components and tools. It is independent from companies in this area of software development.