If you scroll through the readme of the repository, you will find some explanations for the Object Detection networks. As mentioned in my post, the documentation is not complete yet, but most of the possibilities are shown in the various examples. Otherwise I recommend you to go through the code of the library.
If you have a specific question, feel free to ask it directly.
setSkipNMS(): Skips the non-maximum suppression part of the YOLO output (not recommended)
setLabels(): load from txt file or set the labels (names) for the object detection classes, otherwise only the id of the object class is returned in the result
The other two methods
notify() are java related methods, not defined by the library.