return array(
'Symfony\Component\Process' => $vendorDir . '/symfony/process/',
'Monolog' => $vendorDir . '/monolog/monolog/src/',
'Imagine' => $vendorDir . '/imagine/Imagine/lib/',
'Gedmo' => $vendorDir . '/gedmo/doctrine-extensions/lib/',
'Gaufrette' => $vendorDir . '/knplabs/gaufrette/src/',
'Evenement' => $vendorDir . '/evenement/evenement/src',
'Doctrine\ORM' => $vendorDir . '/doctrine/orm/lib/',
'Doctrine\DBAL' => $vendorDir . '/doctrine/dbal/lib/',
'Doctrine\Common' => $vendorDir . '/doctrine/common/lib/',
'Assetic' => $vendorDir . '/kriswallsmith/assetic/src/',
'Analog' => $vendorDir . '/analog/analog/lib/',
);

"psr/log": "1.0.0"

"monolog/monolog": "1.3.*",

Loading composer repositories with package information
Updating dependencies (including require-dev)
  - Installing psr/log (1.0.0)
    Loading from cache

  - Removing monolog/monolog (1.2.1)
  - Installing monolog/monolog (1.3.1)
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'Psr\Log\' => $vendorDir . '/psr/log',

composer dump-autoload

{
  "autoload": {
    "classmap": [
      "path/to/FirstClass.php",
      "path/to/SecondClass.php"
    ]
  }
}

composer dump-autoload -o

<?php
require_once __DIR__ . '/vendor/autoload.php';