Added XCache class loader

src/Symfony/Component/ClassLoader/XCacheUniversalClassLoader.php

@@ -0,0 +1,100 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\ClassLoader;
+
+/**
+ * XCacheUniversalClassLoader implements a "universal" autoloader cached in XCache for PHP 5.3.
+ *
+ * It is able to load classes that use either:
+ *
+ *  * The technical interoperability standards for PHP 5.3 namespaces and
+ *    class names (http://groups.google.com/group/php-standards/web/psr-0-final-proposal);
+ *
+ *  * The PEAR naming convention for classes (http://pear.php.net/).
+ *
+ * Classes from a sub-namespace or a sub-hierarchy of PEAR classes can be
+ * looked for in a list of locations to ease the vendoring of a sub-set of
+ * classes for large projects.
+ *
+ * Example usage:
+ *
+ *     require 'vendor/symfony/src/Symfony/Component/ClassLoader/UniversalClassLoader.php';
+ *     require 'vendor/symfony/src/Symfony/Component/ClassLoader/XCacheUniversalClassLoader.php';
+ *
+ *     use Symfony\Component\ClassLoader\XCacheUniversalClassLoader;
+ *
+ *     $loader = new XCacheUniversalClassLoader('xcache.prefix.');
+ *
+ *     // register classes with namespaces
+ *     $loader->registerNamespaces(array(
+ *         'Symfony\Component' => __DIR__.'/component',
+ *         'Symfony'           => __DIR__.'/framework',
+ *         'Sensio'            => array(__DIR__.'/src', __DIR__.'/vendor'),
+ *     ));
+ *
+ *     // register a library using the PEAR naming convention
+ *     $loader->registerPrefixes(array(
+ *         'Swift_' => __DIR__.'/Swift',
+ *     ));
+ *
+ *     // activate the autoloader
+ *     $loader->register();
+ *
+ * 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 Kris Wallsmith <kris@symfony.com>
+ * @author Kim Hemsø Rasmussen <kimhemsoe@gmail.com>
+ * 
+ *
+ * @api
+ */
+class XCacheUniversalClassLoader extends UniversalClassLoader
+{
+    private $prefix;
+
+    /**
+     * Constructor.
+     *
+     * @param string $prefix A prefix to create a namespace in XCache
+     *
+     * @api
+     */
+    public function __construct($prefix)
+    {
+        if (!extension_loaded('xcache')) {
+            throw new \RuntimeException('Unable to use XCacheUniversalClassLoader as XCache is not enabled.');
+        }
+
+        $this->prefix = $prefix;
+    }
+
+    /**
+     * Finds a file by class name while caching lookups to XCache.
+     *
+     * @param string $class A class name to resolve to file
+     */
+    public function findFile($class)
+    {
+        if (xcache_isset($this->prefix.$class)) {
+            $file = xcache_get($this->prefix.$class);
+        } else {
+            xcache_set($this->prefix.$class, $file = parent::findFile($class));
+        }
+
+        return $file;
+    }
+}