class ClassLoader

ClassLoader implements an PSR-0 class loader

See https://github.com/php-fig/fig-standards/blob/master/accepted/PSR-0.md

$loader = new ClassLoader();

// register classes with namespaces $loader->addPrefix('Symfony\Component', __DIR__.'/component'); $loader->addPrefix('Symfony', __DIR__.'/framework');

// activate the autoloader $loader->register();

// to enable searching the include path (e.g. for PEAR packages) $loader->setUseIncludePath(true);

In this example, if you try to use a class in the Symfony\Component namespace or one of its children (Symfony\Component\Console for instance), the autoloader will first look for the class under the component/ directory, and it will then fallback to the framework/ directory if not found before giving up.

@author Fabien Potencier <fabien@symfony.com> @author Jordi Boggiano <j.boggiano@seld.be>

Hierarchy

Expanded class hierarchy of ClassLoader

4 files declare their use of ClassLoader
bootstrap.inc in drupal/core/includes/bootstrap.inc
Functions that need to be loaded on every Drupal request.
ClassLoaderTest.php in drupal/core/vendor/symfony/class-loader/Symfony/Component/ClassLoader/Tests/ClassLoaderTest.php
DebugClassLoaderTest.php in drupal/core/vendor/symfony/class-loader/Symfony/Component/ClassLoader/Tests/DebugClassLoaderTest.php
DrupalKernel.php in drupal/core/lib/Drupal/Core/DrupalKernel.php
Definition of Drupal\Core\DrupalKernel.

File

drupal/core/vendor/symfony/class-loader/Symfony/Component/ClassLoader/ClassLoader.php, line 40

Namespace

Symfony\Component\ClassLoader
View source
class ClassLoader {
  private $prefixes = array();
  private $fallbackDirs = array();
  private $useIncludePath = false;

  /**
   * Returns prefixes.
   *
   * @return array
   */
  public function getPrefixes() {
    return $this->prefixes;
  }

  /**
   * Returns fallback directories.
   *
   * @return array
   */
  public function getFallbackDirs() {
    return $this->fallbackDirs;
  }

  /**
   * Adds prefixes.
   *
   * @param array $prefixes Prefixes to add
   */
  public function addPrefixes(array $prefixes) {
    foreach ($prefixes as $prefix => $path) {
      $this
        ->addPrefix($prefix, $path);
    }
  }

  /**
   * Registers a set of classes
   *
   * @param string       $prefix The classes prefix
   * @param array|string $paths  The location(s) of the classes
   */
  public function addPrefix($prefix, $paths) {
    if (!$prefix) {
      foreach ((array) $paths as $path) {
        $this->fallbackDirs[] = $path;
      }
      return;
    }
    if (isset($this->prefixes[$prefix])) {
      $this->prefixes[$prefix] = array_merge($this->prefixes[$prefix], (array) $paths);
    }
    else {
      $this->prefixes[$prefix] = (array) $paths;
    }
  }

  /**
   * Turns on searching the include for class files.
   *
   * @param Boolean $useIncludePath
   */
  public function setUseIncludePath($useIncludePath) {
    $this->useIncludePath = $useIncludePath;
  }

  /**
   * Can be used to check if the autoloader uses the include path to check
   * for classes.
   *
   * @return Boolean
   */
  public function getUseIncludePath() {
    return $this->useIncludePath;
  }

  /**
   * Registers this instance as an autoloader.
   *
   * @param Boolean $prepend Whether to prepend the autoloader or not
   */
  public function register($prepend = false) {
    spl_autoload_register(array(
      $this,
      'loadClass',
    ), true, $prepend);
  }

  /**
   * Unregisters this instance as an autoloader.
   */
  public function unregister() {
    spl_autoload_unregister(array(
      $this,
      'loadClass',
    ));
  }

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

  /**
   * Finds the path to the file where the class is defined.
   *
   * @param string $class The name of the class
   *
   * @return string|null The path, if found
   */
  public function findFile($class) {
    if (false !== ($pos = strrpos($class, '\\'))) {

      // namespaced class name
      $classPath = str_replace('\\', DIRECTORY_SEPARATOR, substr($class, 0, $pos)) . DIRECTORY_SEPARATOR;
      $className = substr($class, $pos + 1);
    }
    else {

      // PEAR-like class name
      $classPath = null;
      $className = $class;
    }
    $classPath .= str_replace('_', DIRECTORY_SEPARATOR, $className) . '.php';
    foreach ($this->prefixes as $prefix => $dirs) {
      if (0 === strpos($class, $prefix)) {
        foreach ($dirs as $dir) {
          if (file_exists($dir . DIRECTORY_SEPARATOR . $classPath)) {
            return $dir . DIRECTORY_SEPARATOR . $classPath;
          }
        }
      }
    }
    foreach ($this->fallbackDirs as $dir) {
      if (file_exists($dir . DIRECTORY_SEPARATOR . $classPath)) {
        return $dir . DIRECTORY_SEPARATOR . $classPath;
      }
    }
    if ($this->useIncludePath && ($file = stream_resolve_include_path($classPath))) {
      return $file;
    }
  }

}

Members

Namesort descending Modifiers Type Description Overrides
ClassLoader::$fallbackDirs private property
ClassLoader::$prefixes private property
ClassLoader::$useIncludePath private property
ClassLoader::addPrefix public function Registers a set of classes
ClassLoader::addPrefixes public function Adds prefixes.
ClassLoader::findFile public function Finds the path to the file where the class is defined.
ClassLoader::getFallbackDirs public function Returns fallback directories.
ClassLoader::getPrefixes public function Returns prefixes.
ClassLoader::getUseIncludePath public function Can be used to check if the autoloader uses the include path to check for classes.
ClassLoader::loadClass public function Loads the given class or interface.
ClassLoader::register public function Registers this instance as an autoloader.
ClassLoader::setUseIncludePath public function Turns on searching the include for class files.
ClassLoader::unregister public function Unregisters this instance as an autoloader.