Nicholas Simons

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We describe a behavioural modelling approach based on the concept of a “Protocol Machine”, a machine whose behaviour is governed by rules that determine whether it accepts or refuses events that are presented to it. We show how these machines can be composed in the manner of mixins to model object behaviour and show how the approach provides a basis for(More)
The vision of MDA is to decouple the way that application systems are defined from their deployment platform, thereby ensuring that the investments made in building systems can be preserved even when the underlying technology platforms change. Achieving this vision requires that models are rich enough to capture and represent the behaviour of the(More)
Mainstream object modelling techniques use Statechart Diagrams as a means of modelling object behaviour. Research into how statecharts can be used in the context of class generalization hierarchies has focused on applying the Liskov Substitution Principle (LSP) to statecharts. This approach is problematic, and we describe three reservations. We propose an(More)
State machines can be used to specify the behaviour of objects in a system by describing the relationships between the states of the object and its ability to respond to events presented to it. Suitable choice of semantics for state machines allow multiple machines to be composed in the description of a single object. We describe an extension to this(More)
State Machines are the basic mechanism used to specify the behaviour of objects in UML based object models and admit the possibility of direct animation or execution of a model. Tools that exploit this potential offer the promise of both supporting early validation of a model under development and allowing generation of final code directly from the model.(More)
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