Specializing classes on the fly with the Decorator design pattern

european_citizen.php

/**
 * The contract mapping out some basic attributes
 * that should be visible in all citizen classes
 *
 **/
interface IAmACitizen
{
    public function getName();

    public function getAddress();

    public function getOccupation();
}

/**
 * Our main citizen class
 */
class EuropeanCitizen implements IAmACitizen
{
    protected $occupation;
    protected $name;
    protected $address;

    function __construct( $occupation, $name, $address )
    {
        $this->occupation = $occupation;
        $this->name       = $name;
        $this->address    = $address;
    }

    public function getAddress()
    {
        return $this->address;
    }

    public function getOccupation()
    {
        return $this->occupation;
    }

    public function getName()
    {
        return $this->name;
    }

}

class GermanCitizen
{

    public function germanSpecificAttribute()
    {

    }
}

interface ICanDoWork
{

    public function doWork();
}

abstract class EuropeanWorkerStereotype implements ICanDoWork
{
    public function __construct( IAmACitizen $citizen )
    {
        $this->citizen = $citizen;
    }

    public function getAddress()
    {
        return $this->citizen->getAddress();
    }

    public function getOccupation()
    {
        return $this->citizen->getOccupation();
    }

    public function getName()
    {
        return $this->citizen->getName();
    }
}

class GermanWorkerStereotype extends EuropeanWorkerStereotype
{

    public function doWork()
    {
        return $this->makeCarsForEurope();
    }

    public function makeCarsForEurope()
    {
        return "BMW, Volkswagen, Audi...";

    }
}


class GreekWorkerStereotype extends EuropeanWorkerStereotype
{
    public function doWork()
    {
        return $this->lazeAllDay();
    }

    public function lazeAllDay()
    {
        return "ZZZZZZZZ";

    }
}

class FrenchWorkerStereotype extends EuropeanWorkerStereotype
{

    public function doWork()
    {
        return $this->goOnStrike( null, 5 );
    }

    public function goOnStrike( $reason = null, $numberOfWeeks )
    {
        return "What do we want? I don't know! When do we want it? Now!";
    }
}

class DisplayWorker
{

    public static function display( EuropeanWorkerStereotype $worker )
    {
        echo $worker->getName() . "<br/>";
        echo $worker->getAddress() . "<br/>";
        echo $worker->doWork() . "<br/>";
    }
}

$worker = new EuropeanCitizen( "W", "X", "Y" );

$needAGreekWorker = true;

if ($needAGreekWorker) {
    DisplayWorker::display( new GreekWorkerStereotype( $worker ) );
}

http://dev.linguisticteam.org/2015/05/decorator-design-pattern/