UML图表：我可以在一个图表上多次使用同一个actor吗？
我正在绘制一些图表，我想知道演员在图表中多次出现是否可以接受（以提高图表的透明度）？
I am drawing some diagram, and I am wondering if it is acceptable for the actor to be in diagram more than once (for better transparency of the diagram)?
谢谢
UMLDiagram 是 UMLDiagramElement ，但是 Actor 是否 UmlDiagramElement ，它是元素。 Actor的 UMLDiagramElement 对应物是 UMLShape （显示为图标/数字时）或 UMLClassifierShape （当显示为类框时）。
UMLDiagram is a composition of UMLDiagramElements, however Actor is NOT UmlDiagramElement, it is an Element. The UMLDiagramElement counterpart for Actor is either UMLShape (when shown as icon/figure) or UMLClassifierShape (when shown as a class box).
您必须将 UML模型和 UML图的概念分开。模型是您领域的概念性表示，图是模型的具体视觉表示。
You have to keep the concepts of "UML Model" and "UML Diagram" separate. Model is a conceptual representation of your domain, and diagram is a concrete visual representation of a model.
然后，通过关联将模型和图中的两个元素连接起来（B .2.2）。
The two elements from Model and Diagram are then connected by an association (B.2.2).
关联为N：M（且是单向的），模型不在乎它
The association is N:M (and unidirectional), the model doesn't care that it is being visualized.
据我所知，没有什么可以限制您对单个演员进行多种视觉呈现。
最后，正如托马斯（Thomas）和盖尔特（Geert）所说，这是一个不良习惯。如果您的图是如此复杂，以至于您需要多种表示形式，则应该将其分解。
Lastly as both Thomas and Geert mentioned, it is a bad practice. If your diagram is so complex that you want multiple representations you should probably decompose it.