using System;

    public interface IReader<TParameter, TOutput>

    {

         TOutput Read(TParameter parameter);

    }

    public class Customer : IReader<int, CustomerModel>

    {

         public CustomerModel Read(int parameter)

         {      

             return new CustomerModel() { Id = parameter };

         }

    }

    public class CustomerModel

    {

        public int Id { get; set; }

    }

    public class ReaderProxy<TParameter, TOutput>

        : IReader<TParameter, TOutput>

    {

        private IReader<TParameter, TOutput> reader;

        public ReaderProxy(IReader<TParameter, TOutput> reader)

        {

              this.reader = reader;

        }

        public TOutput Read(TParameter parameter)

        {

            return this.reader.Read(parameter);

        }

    }

    var reader = new ReaderProxy<int, CustomerModel>(new Customer());

    var model = reader.Read(5);

    Console.WriteLine(model.Id);