Laravel如何实现自动加载类

<?php
// autoload.php @generated by Composer
require_once __DIR__ . '/composer/autoload_real.php';
return ComposerAutoloaderInit5586036d8fdd45ae351f9a5ae924a5a3::getLoader();

  if (null !== self::$loader) {
   return self::$loader;
  }

  spl_autoload_register(array('ComposerAutoloaderInit5586036d8fdd45ae351f9a5ae924a5a3', 'loadClassLoader'), true, true);
  self::$loader = $loader = new \Composer\Autoload\ClassLoader();
  spl_autoload_unregister(array('ComposerAutoloaderInit5586036d8fdd45ae351f9a5ae924a5a3', 'loadClassLoader'));

$useStaticLoader = PHP_VERSION_ID >= 50600 && !defined('HHVM_VERSION') && (!function_exists('zend_loader_file_encoded') || !zend_loader_file_encoded());
  if ($useStaticLoader) {
   require_once __DIR__ . '/autoload_static.php';

   call_user_func(\Composer\Autoload\ComposerStaticInit5586036d8fdd45ae351f9a5ae924a5a3::getInitializer($loader));
  } else {
   $map = require __DIR__ . '/autoload_namespaces.php';
   foreach ($map as $namespace => $path) {
    $loader->set($namespace, $path);
   }

   $map = require __DIR__ . '/autoload_psr4.php';
   foreach ($map as $namespace => $path) {
    $loader->setPsr4($namespace, $path);
   }

   $classMap = require __DIR__ . '/autoload_classmap.php';
   if ($classMap) {
    $loader->addClassMap($classMap);
   }
  }

 public function register($prepend = false)
 {
  spl_autoload_register(array($this, 'loadClass'), true, $prepend);
 }

 /**
  * Loads the given class or interface.
  *
  * @param string $class The name of the class
  * @return bool|null True if loaded, null otherwise
  */
 public function loadClass($class)
 {
  if ($file = $this->findFile($class)) {
   includeFile($file);

   return true;
  }
 }