eReaderAdapter.php

<?php 

class eReaderAdapter implements BookInterface {
    private $reader;
    public function __construct(eReaderInterface $reader)
    {
        $this->reader = $reader;
    }
    public function open()
    {
        return $this->reader->turnOn();
    }
    public function turnPage()
    {
        return $this->reader->pressNextButton();
    }
}