A device is a piece of hardware that is equipped with sensors. Geordi knows a set of device types already, so it is easy to get sensor readings from them:
With some Java knowledge, it is easy to add other hardware devices to the Geordi source code:
If you think other people might be interested in your device class, please consider to send a pull request. I will gladly add your class to Geordi’s code base. Please remember to add some lines of documentation as well, so other people will know how to use your class.