The unified coordination language UnCL.

In this paper we show how to use a (subset) of UML as an Unified Coordination Language (UnCL) that is based on a separation of concerns between coordination and computation. As such UnCL provides a general language for the coordination of, in particular, object-oriented applications. The basic idea of UnCL is to use UML as a formalism to specify the `glue code' in terms of state-machines which are added to the classes of the underlying applications. These state-machines describe the coordination of the objects of the underlying applications in terms of sending and receiving events. We introduce a formal semantics of UnCL and discuss its implementation using a new tool for the transformation of XML data which is based on a new Rule Markup Language (RML). Finally, we discuss the incorporation of a more high-level coordination mechanism called MoCha, an exogenous coordination framework for (distributed) communication and collaboration using mobile channels as its mediu

A channel-based coordination model for components

In this paper we present a coordination model for component-based software systems based on the notion of mobile channels, and describe its implementation in the Java language. Channels allow anonymous, and point-to-point communication among components, while mobility allows dynamic reconfiguration of channel connections in a system. This model supports dynamic distributed systems where components can be mobile. It provides an efficient way of interaction among components. Furthermore, our model provides a clear separation between the computational part and the coordination part of a system, allowing the development and description of the coordination structure of a system to be done in a transparent way. Our description of the Java implementation of this coordination model demonstrates that it is self-contained enough for developing component-based systems. However, if desired, our model can be used as a basis to extend other models that focus on other aspects of components that are less related to composition and coordination concerns

Components: From object to mobile channels

In this chapter we introduce a formal model of components which extends objectorientation with additional structuring and abstraction mechanisms to support a modelling discipline based on interfaces. The component model formalizes the concepts of interfaces, roles, connectors, and ports. Components encapsulate their internal class structure and interact only through a certain kind of objects which are called ports. Ports are instances of classes which are represented by roles. Roles export information about the required and provided operations of these classes by means of interfaces. By means of connectors which wire roles of different components together, ports of one component can dynamically create ports of another component. As an example, we show how to model mobile channels for the dynamic reconfiguration and exogenous coordination of components

A Channel-Based Coordination Model for Components

In this paper we present a coordination model for component-based software systems based on the notion of mobile channels, and describe its implementation in the Java language

Modeling the Exogenous Coordination of Mobile Channel based Systems with Petri Nets

AbstractIn this paper, we discuss how to model systems that communicate through and are coordinated by mobile channels. Mainly, we focus on modeling the exogenous coordination behavior imposed by these channels. We use Petri Nets as our modeling language, for they provide a graphically and mathematically founded modeling formalism. We give Petri Nets for a set of mobile channel types. This allows us to construct models of applications, by taking the Petri Net of each component and each mobile channel, and composing them together. For this purpose, we define a special Petri Net composition function. We also discuss analysis and simulation of these models and their exogenous coordination behavior