如何达到构造函数

Question

我正在努力学习java。我需要写一个关于租车的程序。我想访问其值由构造函数给出的变量。我编写了如下代码。它在main的每一行都给出了错误。

public class CarRental {
   public int id;
   /**
    * @param args the command line arguments
    */
   public static void main(String[] args) {
       Customer varCust = new Customer(1,"Joona","Lappeenranta");
       Car varCar = new Car(1,"Mercedes",2013);
       write(id);
   }

   public class Customer {
       public Customer(int idCust, String Name, String Contact) {
           id=idCust;
       }

   public class Car {
       public Car (int idCar, String Model, int myear) {

       }
   }

   public void writethat(int what) {
       System.out.print(what);

   }
}