silverstripe-framework/core/manifest/ClassLoader.php

109 lines
2.5 KiB
PHP

<?php
/**
* A class that handles loading classes and interfaces from a class manifest
* instance.
*
* @package framework
* @subpackage manifest
*/
class SS_ClassLoader {
/**
* @var SS_ClassLoader
*/
private static $instance;
/**
* @var array Map of 'instance' (SS_ClassManifest) and other options.
*/
protected $manifests = array();
/**
* @return SS_ClassLoader
*/
public static function instance() {
return self::$instance ? self::$instance : self::$instance = new self();
}
/**
* Returns the currently active class manifest instance that is used for
* loading classes.
*
* @return SS_ClassManifest
*/
public function getManifest() {
return $this->manifests[count($this->manifests) - 1]['instance'];
}
/**
* Returns true if this class loader has a manifest.
*/
public function hasManifest() {
return (bool)$this->manifests;
}
/**
* Pushes a class manifest instance onto the top of the stack.
*
* @param SS_ClassManifest $manifest
* @param Boolean Marks the manifest as exclusive. If set to FALSE, will
* look for classes in earlier manifests as well.
*/
public function pushManifest(SS_ClassManifest $manifest, $exclusive = true) {
$this->manifests[] = array('exclusive' => $exclusive, 'instance' => $manifest);
}
/**
* @return SS_ClassManifest
*/
public function popManifest() {
$manifest = array_pop($this->manifests);
return $manifest['instance'];
}
public function registerAutoloader() {
spl_autoload_register(array($this, 'loadClass'));
}
/**
* Loads a class or interface if it is present in the currently active
* manifest.
*
* @param string $class
* @return String
*/
public function loadClass($class) {
if ($path = $this->getItemPath($class)) {
require_once $path;
}
return $path;
}
/**
* Returns the path for a class or interface in the currently active manifest,
* or any previous ones if later manifests aren't set to "exclusive".
*
* @return String
*/
public function getItemPath($class) {
foreach(array_reverse($this->manifests) as $manifest) {
$manifestInst = $manifest['instance'];
if ($path = $manifestInst->getItemPath($class)) return $path;
if($manifest['exclusive']) break;
}
return false;
}
/**
* Returns true if a class or interface name exists in the manifest.
*
* @param string $class
* @return bool
*/
public function classExists($class) {
Deprecation::notice('4.0', 'Use ClassInfo::exists.');
return ClassInfo::exists($class);
}
}