'com.company.Advertizing' is not an enclossing class

у меня есть два файла Advertizing.java и Main.java. в первой файле - классы, которые я хочу вызвать в главном втором файле

фрагмент первого файла Мне надо, чтобы код заработал в главном файле. package com.company;

public class Advertizing {
    abstract class newspaper_advertising {
        private String customer;
        private String category;
        private String customortype;
        private String newspaper;
        private String position;
        public String getPosition() {
            return position;
        }
        public String getCustomer() {
            return customer;
        }
        public String getCategory() {
            return category;
        }
        public String getCustomortype() {
            return customortype;
        }
        public String getNewspaper() {
            return newspaper;
        }

        public abstract double FullPayment();
        public abstract double Discount();
        public abstract double CostForPosition();
        newspaper_advertising(String customer, String customortype, String newspaper, String category, String position) {
            this.customer = customer;
            this.customortype = customortype;
            this.newspaper = newspaper;
            this.category = category;
            this.position = position;
        }
    }
    class PhotoAdvertising extends newspaper_advertising {...}
    class StringAdvertizing extends newspaper_advertising {...}

фрагмент второго файла

public class Main extends Advertizing{
    public static void main(String[] args) {
    PhotoAdvertising ad = new PhotoAdvertising(40,"Julia","Person","Travel","Travel","middle");
    System.out.println(ad.FullPayment());
    StringAdvertizing ad1 = new StringAdvertizing(100,"Johnatan D.","Company", "Vogue","Fashion","bottom");
    System.out.println(ad1.FullPayment());
    }
}