Icon class icon_class_computed fas fa-quote-left Related content Figure 9-16: Usage example of item flow decomposition Figure 9-17: Usage example of item flow decomposition Source OMG Systems Modeling Language (SysML) 1.6 Copyright information About Object Management Group copyright in text extracts quoted from OMG specifications for educational purposes Snippet kind INFO UML keywords Connector SysML keywords ItemFlow AssociationBlock Previous snippet Full quote Connectors with item flows can be decomposed by association blocks that have additional item flows. The relationship between an item flow and those in the association block is determined by the modeler. Next snippet Figures 9.16 and 9.17 are examples of item flow decomposition that modelers might choose, but they are not the only possible decompositions and are not required. Related snippets Related snippets (backlinks) Figures 9.16 and 9.17 are examples of item flow decomposition that modelers might choose, but they are not the only possible decompositions and are not required. In Figure 9-16, the item flow classifier (EnginePart) is a supertype of the classifiers of the item flows in the decomposition. The flow properties are all in the types of the nested ports, while the composing item flow summarizes the kinds of items flowing by generalization. In Figure 9-17, the item flow classifier (Engine) composes the classifiers of the items flows in the decomposition from Figure 9-17. The port types have an additional flow property that is not in the nested ports. These are for the flow of the engine, as opposed to its parts. Constraints can be added between the flow properties for the engine and those for the parts, to indicate the flowing parts are inside the flowing engine, or are separate, for example as spare parts. Item flows specify the things that flow between blocks and/or parts and across associations or connectors. Whereas flow properties specify what “can” flow in or out of a block, item flows specify what “does” flow between blocks and/or parts in a particular usage context. This important distinction enables blocks to be interconnected in different ways depending on its usage context. For example, tanks might include a flow property that can accept fluid as an input. In a particular use of tanks, “gasoline” flows across a connector into a tank, and in another use of tanks, “water” flows across a connector into a tank. The item flow in each case specifies what “does” flow on the connector in the particular usage (e.g., gas, water) and the flow property specifies what can flow (e.g., fluid). This enables type matching between the item flows and between flow properties... Visit also Visit also (backlinks) Flags
