使用嵌套泛型类型调用方法

public class Example {
    public static <T> void printList(List<List<T>> nestedList) {
        for (List<T> list : nestedList) {
            for (T item : list) {
                System.out.println(item);
            }
        }
    }

    public static void main(String[] args) {
        List<List<String>> nestedList = new ArrayList<>();
        List<String> list1 = Arrays.asList("A", "B", "C");
        List<String> list2 = Arrays.asList("D", "E", "F");
        nestedList.add(list1);
        nestedList.add(list2);

        printList(nestedList);
    }
}