ProSpec is a tool intended to support business process modeling. It is based on theoretical considerations made at the institute of databases and artificial intelligence (dbai) at the Technical University of Vienna14 and was implemented in the portable language Java by [Aigner 1999] for academic purposes. The screenshot in Figure 50 shows ProSpec with a sample business process loaded. The GUI of ProSpec consists of two parts; a menu bar which provides the whole functionality and a drawing surface. Elements can be added to the drawing surface by selecting one from the menu and then dropping it on the surface by clicking with the mouse on the relevant position. The elements can be connected by selecting the relevant edge (i.e. the flow-type) from the menu and then by clicking on the from-element and afterwards on the to-element. An Element can be positioned by selecting it with the mouse and dragging it to the desired position. An element can be removed by selecting remove from the menu and afterwards clicking on the element. It is not possible to remove an edge directly. To do this either the from-element or the to-element of this connection has to be removed which furthermore removes all connections belonging to this element (This is of course not very efficient since the removed element and the
connections belonging to it have to be defined again). Additionally attributes can be assigned to elements by defining an attribute and then clicking on the relevant element. A connection cannot be selected with the mouse and therefore cannot have attributes. An element cannot be copied and inserted, hence it has to be redefined if it is needed more than once.
Figure 50: ProSpec previous version
ProSpec has been used in an exercise course by students. The feedback (mostly complaints) from these students is a valuable input for further improvements. The
problems users have had with ProSpec are primarily the lack of a well-defined method and procedure and troubles with the tool itself. Particularly, the tool does not support the usual editing functionality (as cut, copy, paste, undo, and so on) users request from a graphical editor, together with inconvenient tool functionality as the lack of a toolbar to select elements. Another source of complaints is the missing collaboration functionality. The students worked in distributed groups and have had the problem how to concurrently develop models or how to merge different parts of the model.
5.1 Relations of ProSpec to the modeling approach
ProSpec supports only a small subset of the modeling approach described in the previous chapter.
Relation of ProSpec to the proposed method
From the method structure developed in the previous section ProSpec supports only the workflow view with the possibility to switch on and off relations to other views, for instance the organisational elements. The metamodel is "hard wired", i.e. that it can only be modified by changing the code and afterwards recompiling the classes. The provided metamodel follows the idea of the event driven process chain (EPC) where activities and logical connectors are connected by events. The workflow view does not support a structuring element such as a subprocess so all elements are presented on a single, flat layer.
Strategic level Goal model Why? Goal view Process level Process model What? Process view How? Workflow view Resource level Resource model Who? Organisation view With what?
Passive resource view
With what?
Application view Figure 51: Relation of ProSpec to the proposed method. ProSpec supports only the workflow view
Relation of ProSpec to the proposed tool functionality
ProSpec supports only the modeling function with the restrictions mentioned before and partially model checking and the repository functionality. The model checking function checks if all activities are connected by control flows and events. None of the administration, evaluation and transformation functions are supported. Figure 52 shows the proposed tool architecture and the supported functions, where N=no support, P=partial support, and S=support. The list shows that ProSpec supports only the
Administration Modeling Evaluation Transformation Customizing N Modeling S Static
analysis N Resource mgmt. System N Version management N Model checking P Simulation N Workflow mgmt. System N
Authorisation N Configuration N Other modeling tool N
Code generation N
Paper document N
Hypertext document N
Repository P
Figure 52: Relation of ProSpec to the proposed tool.
5.2 Proposed Improvements to ProSpec
The current version of ProSpec hardly allows the usage of the tool in “real world” modeling projects. The rest of this paper will focus on some of the deficiencies and will provide possible solutions to improve the usability of ProSpec. The first problem considered is the workflow view and the constituting elements, i.e. the events, the
activities, the flow of control, and the logical connectors. This is a major problem since the evaluation functionality (static analysis and simulation) as well as an important part of the transformation functionality (export to workflow management systems) depend largely on correctly defined workflows. The second problem which is being tackled is the navigation functionality and the separation of a model in different views which will allow to structure the models according to the proposed method. A third problem considered concerns improvements to the GUI to enhance the usability aspect. The reason, why these problems have been selected, is to strengthen existing functions before introducing new
functionality. A further reason is, that only a tool that offers sufficient convenience for users can be validated in "real world" projects.