I am working on making a very brief demo as a proof-of-concept for my company. I am trying to model a decision process for the location of an incoming trailer in a warehouse's yard. Based on specifications such as contents (will the item need to be refrigerated), length, weight, etc, the model will help a warehouse worker decide where to put the trailer. I have used service tasks to represent the attributes and make a decision since my company is hoping to integrate Activiti with the existing software. I am purely running a demo not integrated with our software but I made a simple Java class with a constructor and getter/setter methods for the attributes. For the "Refrigerated?" service task, I chose expression for the task type and entered "#{Trailer.isRefrigerated()}". I have run the unit test and no matter what I do, this always seems to be the culprit for the JUnit test failing. I have done research for about a week now, tried many options, and still have gotten no where. The console keeps pointing to that expression being an Unknown Property. Please help! I do not have much experience with Activiti and very limited knowledge of BPMNs in general. Any help is greatly appreciated.