index.php

<?php
/**
 * This is the Front Controller.
 * The Front Controller decides which action to run.
 *
 * This particular Front Controller defines a route table, which says
 * which defines which URLs map to which actions.
 *
 * @author Damien Walsh <me@damow.net>
 */
require_once 'vendor/autoload.php';

// Define the routes table
$routes = array(
    '/\/hello\/(.+)/' => array('HelloController', 'helloAction')
);

// Decide which route to run
foreach ($routes as $url => $action) {

    // See if the route matches the current request
    $matches = preg_match($url, $_SERVER['REQUEST_URI'], $params);

    // If it matches...
    if ($matches > 0) {

        // Run this action, passing the parameters.
        $controller = new $action[0];
        $controller->{$action[1]}($params);

        break;
    }
}