Method placeUnit

InventorySystem.java:19–28

(Unit unit)

    }

    public static void placeUnit(Unit unit) {
        for (Map.Entry<Location, Unit> entry: locationMap.entrySet()){
            // if (SimpleStrategy.works())
            //get lock on entry.getKey()
                if(entry.getValue()==null){
                    unit.locationId = entry.getKey().id;
                }
                //release lock
            }
    }

    public static void removeUnit(Product product) {
        for (Map.Entry<Location, Unit> entry: locationMap.entrySet()){