External liblary class inside plugin controller I have external library handling connection to mail delivery system. Its just php class. How do i include and use this class inside craft plugin controller?

library.php:

class mail_delivery{
    //code
}


plugin/controllers/controller.php:

namespace Craft;

class controller extends BaseController
{

    public function init()
    {
        require_once 'library.php';
    }

    public function method(){
        $object = $rest = new mail_delivery();
    }


I get PHP error:


  ( ! ) Fatal error: Class 'Craft\FmRestAPI' not found in
  C:\xampp\htdocs\mmimport\craft\plugins\freshmailintegration\controllers\FreshmailIntegration_EmailController.php
  on line 27


Is this some kind of namespace issue?
Is this some kind of namespace issue?


Yes.  If the class you're trying to instantiate is in a namespace, you'd need to indicate that:

$object = $rest = new \the\library\class\namespace\mail_delivery();


If it does not use namespaces, it's probably in the global namespace:

$object = $rest = new \mail_delivery();


If you do it like in your example:

$object = $rest = new mail_delivery();


Then PHP will assuming it's in the current file's namespace (Craft) and you'll get the error that you see.