Symfony
sponsored by SensioLabs
Menu
  • About
  • Documentation
  • Screencasts
  • Cloud
  • Certification
  • Community
  • Businesses
  • News
  • Download
  1. Home
  2. Documentation
  3. Components
  4. Class Loader
  5. The Class Map Generator
  • Documentation
  • Book
  • Reference
  • Bundles
  • Cloud
Search by Algolia

Table of Contents

  • Generating a Class Map
  • Dumping the Class Map

The Class Map Generator

Edit this page

Warning: You are browsing the documentation for Symfony 3.0, which is no longer maintained.

Read the updated version of this page for Symfony 6.2 (the current stable version).

The Class Map Generator

Loading a class usually is an easy task given the PSR-0 and PSR-4 standards. Thanks to the Symfony ClassLoader component or the autoloading mechanism provided by Composer, you don't have to map your class names to actual PHP files manually. Nowadays, PHP libraries usually come with autoloading support through Composer.

But from time to time you may have to use a third-party library that comes without any autoloading support and therefore forces you to load each class manually. For example, imagine a library with the following directory structure:

1
2
3
4
5
6
7
8
9
library/
├── bar/
│   ├── baz/
│   │   └── Boo.php
│   └── Foo.php
└── foo/
    ├── bar/
    │   └── Foo.php
    └── Bar.php

These files contain the following classes:

File Class Name
library/bar/baz/Boo.php Acme\Bar\Baz
library/bar/Foo.php Acme\Bar
library/foo/bar/Foo.php Acme\Foo\Bar
library/foo/Bar.php Acme\Foo

To make your life easier, the ClassLoader component comes with a ClassMapGenerator class that makes it possible to create a map of class names to files.

Generating a Class Map

To generate the class map, simply pass the root directory of your class files to the createMap() method:

1
2
3
use Symfony\Component\ClassLoader\ClassMapGenerator;

var_dump(ClassMapGenerator::createMap(__DIR__.'/library'));

Given the files and class from the table above, you should see an output like this:

1
2
3
4
5
6
7
Array
(
    [Acme\Foo] => /var/www/library/foo/Bar.php
    [Acme\Foo\Bar] => /var/www/library/foo/bar/Foo.php
    [Acme\Bar\Baz] => /var/www/library/bar/baz/Boo.php
    [Acme\Bar] => /var/www/library/bar/Foo.php
)

Dumping the Class Map

Writing the class map to the console output is not really sufficient when it comes to autoloading. Luckily, the ClassMapGenerator provides the dump() method to save the generated class map to the filesystem:

1
2
3
use Symfony\Component\ClassLoader\ClassMapGenerator;

ClassMapGenerator::dump(__DIR__.'/library', __DIR__.'/class_map.php');

This call to dump() generates the class map and writes it to the class_map.php file in the same directory with the following contents:

1
2
3
4
5
6
<?php return array (
'Acme\\Foo' => '/var/www/library/foo/Bar.php',
'Acme\\Foo\\Bar' => '/var/www/library/foo/bar/Foo.php',
'Acme\\Bar\\Baz' => '/var/www/library/bar/baz/Boo.php',
'Acme\\Bar' => '/var/www/library/bar/Foo.php',
);

Instead of loading each file manually, you'll only have to register the generated class map with, for example, the MapClassLoader:

1
2
3
4
5
6
7
8
9
10
11
12
use Symfony\Component\ClassLoader\MapClassLoader;

$mapping = include __DIR__.'/class_map.php';
$loader = new MapClassLoader($mapping);
$loader->register();

// you can now use the classes:
use Acme\Foo;

$foo = new Foo();

// ...

Note

The example assumes that you already have autoloading working (e.g. through Composer or one of the other class loaders from the ClassLoader component.

Besides dumping the class map for one directory, you can also pass an array of directories for which to generate the class map (the result actually is the same as in the example above):

1
2
3
4
5
6
use Symfony\Component\ClassLoader\ClassMapGenerator;

ClassMapGenerator::dump(
    array(__DIR__.'/library/bar', __DIR__.'/library/foo'),
    __DIR__.'/class_map.php'
);
This work, including the code samples, is licensed under a Creative Commons BY-SA 3.0 license.
We stand with Ukraine.
Version:
No stress: we've got you covered with our 116 automated quality checks of your code

No stress: we've got you covered with our 116 automated quality checks of your code

Be trained by SensioLabs experts (2 to 6 day sessions -- French or English).

Be trained by SensioLabs experts (2 to 6 day sessions -- French or English).

↓ Our footer now uses the colors of the Ukrainian flag because Symfony stands with the people of Ukraine.

Avatar of Rodrigo Capilé, a Symfony contributor

Thanks Rodrigo Capilé (@rcapile) for being a Symfony contributor

1 commit • 16 lines changed

View all contributors that help us make Symfony

Become a Symfony contributor

Be an active part of the community and contribute ideas, code and bug fixes. Both experts and newcomers are welcome.

Learn how to contribute

Symfony™ is a trademark of Symfony SAS. All rights reserved.

  • What is Symfony?
    • Symfony at a Glance
    • Symfony Components
    • Case Studies
    • Symfony Releases
    • Security Policy
    • Logo & Screenshots
    • Trademark & Licenses
    • symfony1 Legacy
  • Learn Symfony
    • Symfony Docs
    • Symfony Book
    • Reference
    • Bundles
    • Best Practices
    • Training
    • eLearning Platform
    • Certification
  • Screencasts
    • Learn Symfony
    • Learn PHP
    • Learn JavaScript
    • Learn Drupal
    • Learn RESTful APIs
  • Community
    • SymfonyConnect
    • Support
    • How to be Involved
    • Code of Conduct
    • Events & Meetups
    • Projects using Symfony
    • Downloads Stats
    • Contributors
    • Backers
  • Blog
    • Events & Meetups
    • A week of symfony
    • Case studies
    • Cloud
    • Community
    • Conferences
    • Diversity
    • Documentation
    • Living on the edge
    • Releases
    • Security Advisories
    • SymfonyInsight
    • Twig
    • SensioLabs
  • Services
    • SensioLabs services
    • Train developers
    • Manage your project quality
    • Improve your project performance
    • Host Symfony projects
    Deployed on
Follow Symfony
Search by Algolia