public class A <T> extends B <List<T>>{

private int b;

}

public class B<T> {

private T date;

public T getDate() {

return date;

}

public void setDate(T date) {

this.date = date;

}

}

public class C {

public static void main(String[] args) {

A<String> a = new A<String>();

List<String> list = a.getDate();

}

}

给A提供类型就相当于给T date;提供类型