接口(这是好几个类分开写)

Api

public interface Api {    public static final String url = "http://result.eolinker.com/iYXEPGn4e9c6dafce6e5cdd23287d2bb136ee7e9194d3e9?uri=evaluation";}

IMainActivity 
public interface IMainActivity {    public void showList(List<GoosBean.DataBean> groupList, List<List<GoosBean.DataBean.DatasBean>> childList);}
IMainModel
public interface IMainModel {    public void getGoods(OnNetListener<GoosBean> onNetListener);}
OnNetListener
public interface OnNetListener<T> {    public void onSuccess(T t);    public void onFailure(Exception e);}