Talks Workshops Register
  1. Home
  2. Documentation
  3. Components
  4. Class Loader
  5. Cache a Class Loader
WARNING: You are browsing the documentation for Symfony 2.6 which is not maintained anymore. Consider upgrading your projects to Symfony 4.3.

Cache a Class Loader

2.6 version
Maintained
3.4
Unmaintained
2.2 2.3 2.4 2.5 2.7 2.8 3.0 3.1 3.2 3.3

Cache a Class Loader

Introduction

Finding the file for a particular class can be an expensive task. Luckily, the ClassLoader component comes with two classes to cache the mapping from a class to its containing file. Both the ApcClassLoader and the XcacheClassLoader wrap around an object which implements a findFile() method to find the file for a class.

Note

Both the ApcClassLoader and the XcacheClassLoader can be used to cache Composer's autoloader.

ApcClassLoader

ApcClassLoader wraps an existing class loader and caches calls to its findFile() method using APC:

 1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
require_once '/path/to/src/Symfony/Component/ClassLoader/ApcClassLoader.php';

// instance of a class that implements a findFile() method, like the ClassLoader
$loader = ...;

// sha1(__FILE__) generates an APC namespace prefix
$cachedLoader = new ApcClassLoader(sha1(__FILE__), $loader);

// register the cached class loader
$cachedLoader->register();

// deactivate the original, non-cached loader if it was registered previously
$loader->unregister();

XcacheClassLoader

XcacheClassLoader uses XCache to cache a class loader. Registering it is straightforward:

 1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
require_once '/path/to/src/Symfony/Component/ClassLoader/XcacheClassLoader.php';

// instance of a class that implements a findFile() method, like the ClassLoader
$loader = ...;

// sha1(__FILE__) generates an XCache namespace prefix
$cachedLoader = new XcacheClassLoader(sha1(__FILE__), $loader);

// register the cached class loader
$cachedLoader->register();

// deactivate the original, non-cached loader if it was registered previously
$loader->unregister();

This work, including the code samples, is licensed under a Creative Commons BY-SA 3.0 license.