think\Loader::registerComposerLoader PHP Method

    private static function registerComposerLoader()
    {
        if (is_file(VENDOR_PATH . 'composer/autoload_namespaces.php')) {
            $map = (require VENDOR_PATH . 'composer/autoload_namespaces.php');
            foreach ($map as $namespace => $path) {
                self::addPsr0($namespace, $path);
            }
        }
        if (is_file(VENDOR_PATH . 'composer/autoload_psr4.php')) {
            $map = (require VENDOR_PATH . 'composer/autoload_psr4.php');
            foreach ($map as $namespace => $path) {
                self::addPsr4($namespace, $path);
            }
        }
        if (is_file(VENDOR_PATH . 'composer/autoload_classmap.php')) {
            $classMap = (require VENDOR_PATH . 'composer/autoload_classmap.php');
            if ($classMap) {
                self::addClassMap($classMap);
            }
        }
        if (is_file(VENDOR_PATH . 'composer/autoload_files.php')) {
            $includeFiles = (require VENDOR_PATH . 'composer/autoload_files.php');
            foreach ($includeFiles as $fileIdentifier => $file) {
                if (empty(self::$autoloadFiles[$fileIdentifier])) {
                    __require_file($file);
                    self::$autoloadFiles[$fileIdentifier] = true;
                }
            }
        }
    }