ArrayList<Person> peopleList;
ArrayList<Place> placeList;

public static void sort(ArrayList list){
  sortList(list);
}
public static void sortList(ArrayList<Comparable> list)
{
   //Code here
}

public static void sort(ArrayList<Comparable> list){
  sortList(list);
}

Error:(59, 14) java: method sort in class Sorts cannot be applied to given types;
  required: java.util.ArrayList<java.lang.Comparable>
  found: java.util.ArrayList<Passenger>
  reason: actual argument java.util.ArrayList<Passenger> cannot be converted to java.util.ArrayList<java.lang.Comparable> by method invocation conversion