Hi Folks, I am new to OptaPlanner, so please forgive me if this is a stupid question. I developed a project to solve a worker assignment problem based on OptaPlanner. I have a java class "Demand" which has the information of capacity needed for each shift. I added it to the solution class as a problem fact, since it should never be changed. Then I wrote rules saying that when the supply on that shift can not satisfy the demand there will be a point loss. The problem I met is that when stepping into local search phase, the solver can not access to this class. For instance, I have the following rule: rule " test rule" when $s : Shift($i : index) $d : Demand(shift.getIndex() == $i) then System.out.println("Test rule fired."); end fired. Does anyone have any thoughts on why this happened and how I should solve this problem? I will appreciate your help. Thanks,