FlexLoader __autoload

Een voorbeeld autload functie, ook kan je natuurlijk zelf een functie maken die in SPL te hangen valt
[code]
<?php
/**
 * Automagic PHP autoload function
 *
 * @param string $class_name
 * @return bool
 */
function __autoload($class_name)
{
	static $flexloader = null;
	
	if(!isset($flexloader)) {
		$cachepath = './cache/flexloader.cache.php';
		$classespath = realpath('./classes');
		// Cachefile path, directories to scan, extensions, ignore hidden files, follow symlinks
		$flexloader = new FlexLoader($cachepath, array($classespath));
	}
	return $flexloader->loadClass($class_name);
}
[/code]


[code]
<?php
/**
 * FlexLoader
 * 
 * @author Christiaan Baartse <[email protected]>
 * @version 0.0.2
 * @since 28/02/2008
 */
class FlexLoader {
	
	/**
	 * Directories to scan
	 *
	 * @var array
	 */
	protected $directories;
	
	/**
	 * Cache filename
	 *
	 * @var string
	 */
	protected $cache_file;
	
	/**
	 * Class to file mapping
	 *
	 * @var array
	 */
	protected $class2file;
	
	/**
	 * Extensions to scan
	 *
	 * @var array
	 */
	protected $extensions;
	
	/**
	 * Enable scanning of hidden files
	 *
	 * @var bool
	 */
	protected $hidden;
	
	/**
	 * Enable following of symlinks
	 *
	 * @var bool
	 */
	protected $symlinks;
		
	/**
	 * Construct
	 *
	 * @param string $cache_file
	 * @param array $directories
	 * @param array $extensions
	 * @param bool $hidden
	 * @param bool $symlinks
	 */
	public function __construct($cache_file = 'flexloader.cache.php', $directories = array('classes'), $extensions = array('.php'), $hidden = false, $symlinks = true)
	{
		$this->cache_file = $cache_file;
		$this->directories = $directories;
		$this->extensions = $extensions;
		$this->hidden = $hidden;
		$this->symlinks = $symlinks;
		
		if( ! file_exists($this->cache_file) && ! $this->createCache()) {
			throw new Exception("FlexLoader: Couldn't create cache '".$this->cache_file."'");
		}else{
			if(include($this->cache_file)) {
				$this->class2file = @$flexloader_classes;
			}else{
				throw new Exception("FlexLoader: Couldn't load cache from '".$this->cache_file."'");
			}
		} 	
	}
	
	/**
	 * Load file containing the given class
	 *
	 * @param string $class_name
	 * @return boolean
	 */
	public function loadClass($class)
	{
		$class = strtolower($class);
		
		if(isset($this->class2file[$class]) && include($this->class2file[$class])) {
			return TRUE;
		}
		else{ //Comment out this whole else on production sites
			$this->class2file = array();
			$this->createCache();
			if(isset($this->class2file[$class]) && include($this->class2file[$class])) {
				return TRUE;
			}
		}// So untill here

		throw new Exception(__CLASS__." couldn't ".__METHOD__." ".$class);
	}
	
	/**
	 * Create the cachefile
	 *
	 * @return bool
	 */
	public function createCache()
	{
		foreach($this->directories as $directory) {
			$this->parseDirectory($directory.'/');
		}
		
		$cache = "<?php\n\$flexloader_classes = ";
		$cache.= var_export($this->class2file, true);
		$cache.= ';';		
		file_put_contents($this->cache_file, $cache);
		
		return TRUE;
	}
	
	/**
	 * Parse Directory for files containing classes
	 *
	 * @param string $directory Pathname of directory
	 * @return bool
	 */
	protected function parseDirectory($directory)
	{
		if( ! is_dir($directory)) return FALSE;
		if( ! $dhandle = opendir($directory)) return FALSE;
		while(($file = readdir($dhandle)) !== false) {
			if($file[0] == '.' && ! $this->hidden) continue;

			$file_path = $directory.$file;
			if(is_dir($file_path)){
				if($file == '.' || $file == '..') continue;
				$this->parseDirectory($file_path.'/');			
			}elseif($this->symlinks && is_link($file_path)){
				$this->parseDirectory($file_path.'/');
			}elseif(is_file($file_path)){
				if(empty($this->extensions) || in_array(substr($file, strrpos($file, '.')), $this->extensions)) {
					preg_match_all('~^\s*(?:abstract\s+|final\s+)?(?:class|interface)\s+(\w+)~mi', file_get_contents($file_path), $result);
					if( ! empty($result[1])){
						foreach($result[1] as $class_name) {
							$this->class2file[strtolower($class_name)] = $file_path;
						}
					}
				}
			}
		}				
		return TRUE;
	}
	
}
[/code]