A factory class for getting the latest version of a class

gistfile1.txt

<?php	
if ( !function_exists( 'bfi_thumb' ) ) {
	function bfi_thumb() {
		return BFI_Class_Factory::getNewestVersion( 'BFI_Thumb' )->run();
	}
}

if ( !class_exists( 'BFI_Class_Factory' ) ) {
class BFI_Class_Factory {
	public static $versions = array();
	public static $latestClass = array();
	
	public static function addClassVersion( $baseClassName, $className, $version ) {
		if ( empty( self::$versions[$baseClassName] ) ) {
			self::$versions[$baseClassName] = array();
		}
		self::$versions[$baseClassName][] = array( 
			'class' => $className, 
			'version' => $version
		);
	}
	
	public static function getNewestVersion( $baseClassName ) {
		if ( empty( self::$latestClass[$baseClassName] ) ) {
	        usort( self::$versions[$baseClassName], array( __CLASS__, "versionCompare" ) );	
			self::$latestClass[$baseClassName] = new self::$versions[$baseClassName][0]['class'];
			unset( self::$versions[$baseClassName] );
		}
		return self::$latestClass[$baseClassName];
	}
	
	public static function versionCompare( $a, $b ) {
		return version_compare( $a['version'], $b['version'] ) == 1 ? -1 : 1;
	}
}
}

if ( !class_exists( 'BFI_Thumb_2_0' ) ) {
	BFI_Class_Factory::addClassVersion( 'BFI_Thumb', 'BFI_Thumb_2_0', '2.0' );
	
	class BFI_Thumb_2_0 {
		public function run() {
			echo "Running v2.0";
		}
	}
	
}