The goal of each AbstractRole is to contribute to (a part of) the requirements of the organisation within which it is defined. The behaviour of an AbstractRole is specified within a Role Plan. The goal of this activity is to conceive for each role a plan that could fulfil the part of the organisation requirements that have been delegated to the role under study. In this context a plan describes how a goal can be achieved. It is the description of how to combine and order interactions, external events, and RoleTasks to fulfil a (part of a) requirement (the goal). A RoleTask is the specification of a parameterized behaviour in form of a coordinated sequence of subordinate units (a RoleTask can be composed of other RoleTasks). The definition of these units can be based on capacities, required by the role.
Plans of roles behaviour are deduced from the Scenario description and the results of organisations, roles and interactions identification activities.
Each Role Plan is described using an UML activity diagram, where swimlanes are used to partition activities of different roles and one swimlane is left for hosting external events. The diagram can be drawn at the single role level of abstraction (this means that one unique role is described, see figure ??) or also at the organisational level of abstraction (all the roles of an organisation are depicted, each one with its own swimlane, see figure ??). The swimlanes are dedicated to the role under study and they contain activities symbolizing RoleTasks (they constitute, together with their relationships, the actual plan of each of the studied roles). The last (usually the left or right most one) swimlane contains activities representing Roletasks of other roles of the same organisation that interact with the studied role. Each arrow crossing the line between the two swimlanes corresponds to an interaction between the two associated roles.
|Figure 13: Two templates for the Role Plan Description activity diagram |
MAS Metamodel Elements
Define(RolePlan), Define(RoleTask), Quote(Role), Relate(RoleTask, AbstractRole).
Work to be done
Previous activities describe the various interactions identified among roles defined in a given organisation. The goal is now to provide each role with a first description of a behaviour able to fulfill a part of the requirements of its organisation and corresponding to the previously described plan. Each line crossing the dashed line between Designed Role and Other Roles the swimlane corresponds to an interaction and thus should match one of the previously identified interations.
At this step, we focus on each role in order to define a plan that may accomplish the requirements coming from the previous parts of the design. The first task in this activity consists in detailing responsibilities assigned to the currently designed role. Then for each of them, a set of RoleTasks has to be identified for accomplishing the assigned requirements. The final step consists in determining transitions between the various activities and the set of associated conditions. In a second iteration each task will be examined to be eventually decomposed and in order to determine if it requires something external to the role. If this is the case then a new capacity ieswill be created and the role will refer to that.
The Interaction and Role identification activity is a starting point for conceiving a complete specification of an organisation. Each previously identified Interaction should appear in the plan as part of the control flow or as an event crossing the partition. This allows to check if the current plan effectively fulfils the previously described scenario.
The description of role plans associated to the Team Simulation organisation is presented in figure 14. The activity diagram is partitioned according to the different roles of the organisation, a supplementary partition line is added to represented the part of the system external to the designed organisation. Interactions with this external part are represented by adopting an event-driven perspective.
|Figure 14: Plan of the Team Simulation Organisation |