Creating subclass of a class in java

Question

edited version. I think my question was not clear. So, i have made some changes. I have a package named "module 6". Under module 6, there are two separate classes named "EarthquakeCityMap" and "CommonMarker". Inside the EarthquakeCityMap Class there are declaration for List, Strings. For eg:

 public class EarthquakeCityMap {

private UnfoldingMap map;

private List<Marker> cityMarkers;
private List<Marker> quakeMarkers;
private List<Marker> countryMarkers;
private CommonMarker lastSelected;


   }

I understand the declaration "List" but could not understand "private CommonMarker lastSelected"

I do not want to give you trouble. But if you could not understand this, here is the link for the entire source code https://github.com/areszhao/UnfoldingMaps/tree/master/src/module6

Thank you

Answer 1

这意味着，一个EarthquakeCityMap类有一个CommonMarker称为lastSelected，并且访问lastSelected对象被限制为内EarthquakeCityMap类。