Get the list reference type

I have a problem to get the type of a list. The problem is While declaring I'm not specifying the type. I'm setting it only at run time.

I have a POJO class

public class MyObject {

    private String name;
    private List list;

//getter and setter
}

I have followed this SO question and tried my below code

public class ListType {

    public static void main(String[] args) throws NoSuchFieldException, SecurityException {
        ListType listType = new ListType();
        List<Integer> list = new ArrayList<Integer>();
        MyObject myObject = new MyObject();
        myObject.setList(list);
        listType.initialize(myObject);
    }

    private void initialize(MyObject myObject) throws NoSuchFieldException, SecurityException {
        List list = myObject.getList();
        ListType listType = new ListType();
        listType.getListType(list);
    }

    private void getListType(List list) throws NoSuchFieldException, SecurityException {
        Field stringListField = MyObject.class.getDeclaredField("list");
        ParameterizedType stringListType = (ParameterizedType) stringListField.getGenericType();
        Class<?> stringListClass = (Class<?>) stringListType.getActualTypeArguments()[0];
        System.out.println(stringListClass);
    }

}

Then I am getting following exception

Exception in thread "main" java.lang.ClassCastException: java.lang.Class cannot be cast to java.lang.reflect.ParameterizedType
    at com.sample.listtype.ListType.getListType(ListType.java:26)
    at com.sample.listtype.ListType.initialize(ListType.java:21)
    at com.sample.listtype.ListType.main(ListType.java:15)

If i declare the list variable with a specific type in MyObject class,

private List<Integer> list;

I'm getting proper result. But how to get the type if I'm setting at run time?