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[READ-ONLY] Subtree split of the Symfony ClassLoader Component -- clone into Symfony/Component/ (master at symfony/symfony)
Latest commit 05ad699 @nicolas-grekas nicolas-grekas Merge branch '2.8'
* 2.8:
  Always enable clock-mock for HttpFoundation
  [ClassLoader] Fix parsing namespace when token_get_all() is missing
  Bug #16343 [Router] Too many Routes ?
  Fixes the stack traces of the deprecation logs
  fix unused variable warning
  [Translation][Form] Do not translate form labels and placeholders when 'translation_domain' is false
  add composer exclude-from-classmap for new 2.8 components
  [Yaml] sync changelog and upgrade files
  [Debug] Ensure class declarations are loaded only once
  Minor design tweaks for the Logs and Doctrine profiler panels


ClassLoader Component

ClassLoader loads your project classes automatically if they follow some standard PHP conventions.

The ClassLoader object is able to autoload classes that implement the PSR-0 standard or the PEAR naming convention.

First, register the autoloader:

require_once __DIR__.'/src/Symfony/Component/ClassLoader/ClassLoader.php';

use Symfony\Component\ClassLoader\ClassLoader;

$loader = new ClassLoader();

Then, register some namespaces with the addPrefix() method:

$loader->addPrefix('Symfony', __DIR__.'/src');
$loader->addPrefix('Monolog', __DIR__.'/vendor/monolog/src');

The addPrefix() method takes a namespace prefix and a path where to look for the classes as arguments.

You can also register a sub-namespaces:

$loader->addPrefix('Doctrine\\Common', __DIR__.'/vendor/doctrine-common/lib');

The order of registration is significant and the first registered namespace takes precedence over later registered one.

You can also register more than one path for a given namespace:

$loader->addPrefix('Symfony', array(__DIR__.'/src', __DIR__.'/symfony/src'));

Alternatively, you can use the addPrefixes() method to register more than one namespace at once:

    'Symfony' => array(__DIR__.'/src', __DIR__.'/symfony/src'),
    'Doctrine\\Common' => __DIR__.'/vendor/doctrine-common/lib',
    'Doctrine' => __DIR__.'/vendor/doctrine/lib',
    'Monolog' => __DIR__.'/vendor/monolog/src',

For better performance, you can use the APC class loader:

require_once __DIR__.'/src/Symfony/Component/ClassLoader/ClassLoader.php';
require_once __DIR__.'/src/Symfony/Component/ClassLoader/ApcClassLoader.php';

use Symfony\Component\ClassLoader\ClassLoader;
use Symfony\Component\ClassLoader\ApcClassLoader;

$loader = new ClassLoader();
$loader->addPrefix('Symfony', __DIR__.'/src');

$loader = new ApcClassLoader('apc.prefix.', $loader);

Furthermore, the component provides tools to aggregate classes into a single file, which is especially useful to improve performance on servers that do not provide byte caches.


You can run the unit tests with the following command:

$ cd path/to/Symfony/Component/ClassLoader/
$ composer install
$ phpunit
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