Object Orientation with Parallelism and Persistence

Both object orientation and parallelism are modern programming paradigms which have gained much popularity in the last 10-15 years. Object orientation raises hopes for increased productivity of software generation and maintenance methods. Parallelism can serve to structure a problem but also promises faster program execution. The two areas of computing science in which these paradigms play the most prominent role are programming languages and databases. In programming languages, one can take an academic approach with a primary focus on the generality of the semantics of the language constructs which support the respective paradigm. In databases, one is willing to restrict the power of the constructs in the interest of increased efficiency. Inter- and intra-object parallelism have received an increasing amount of attention in the last few years by researchers in the area of object- oriented programming. At first glance, an object is very similar to a process which offers services to other processes and demands services from them. It has, however, transpired that object-oriented concepts cause problems when combined with parallelism. In programming languages, the introduction of parallelism and the synchronization constraints it brings with it can get in the way of code reusability. In databases, the combination of object orientation and parallelism requires, for example, a generalization of the transaction model, new approaches to the specification of information systems, an implementation model of object communication, and the design of an overall system architecture. There has been insufficient communication between researchers in programming languages and in databases on these issues. Object Orientation with Parallelism and Persistence grew out of a Dagstuhl Seminar of the same title in April 1995 whose goal it was to put the new research area `object orientation with parallelism' on an interdisciplinary basis. Object Orientation with Parallelism and