I’m working on two projects right now that both involve business objects that undergo several state transitions based on actions taken by a user. We quickly turned to State models to help conceptualize all of the possible object states, possible transitions between them, and the actions that trigger the transitions. While those models were incredibly helpful in defining our transition requirements for the objects themselves, we also realized that developers needed a larger context for the transitions within the business process as a whole, so they could better understand the preconditions and user inputs that contribute to the transitions (the state models alone wouldn’t be enough). We already had a set of high-level models on the project, including a Business Objectives Model, Feature Tree and set of current and future state process flows (among others), and needed a way to tie in our lower level state models in a simple way (as opposed to a detailed traceability matrix).

Skittles, or round circles with either color or text that can overlay additional data on another model, can be incredibly useful when you want to tie two models together in a visual way. With our newly validated state table and state diagram, of the models we had created, we determined that we could most easily integrate the state transitions with the existing process flows (which included the actions that drove transitions between our objects’ states). For every process step that triggered a change in state, we added a little round colored circle to the top corner and included the text of the new state that would result at the end of the process step. Not only were we able to better model the preconditions based on processes for each state change, but we were also able to identify a few state transitions that were missing process steps! Without including the very detailed models I created for these particular projects, here are a few process steps with the state skittle:

Note that skittles can be used in a variety of ways and on a variety of models – remember this as a way to add supplemental information to add even more clarity to your requirements! Also remember to include your skittles in a key so the consumers of your documents know what you are talking about.