I have 19 years experience in programming with 10 years in java. I have designed WareHouse management system for large manufacturing unit. The warehouse is commonly used by four different units of the factory. The application manages the inventory record collectively and separately, with automatic inter-unit transfers. The software also generates inventory evaluation, on FIFO, and moving average methods. The reports generated by the software has successfully been verified by annual audit teams for last 4 years.
POS sofware is upto some extent like warehouse inventory system with some exceptions, in pricing and evaluation. The scale can be used as input medium if it can provide data to the application in some predefined format (text file. direct connection to database etc). The modern systems normally use TCP for communication with such devices. If you have such details please provide more details about the project so that we can discuss it further