PayPal\Common\ReflectionUtil::propertyAnnotations PHP Method

    public static function propertyAnnotations($class, $propertyName)
    {
        $class = is_object($class) ? get_class($class) : $class;
        if (!class_exists('ReflectionProperty')) {
            throw new \RuntimeException("Property type of " . $class . "::{$propertyName} cannot be resolved");
        }
        if ($annotations =& self::$propertiesType[$class][$propertyName]) {
            return $annotations;
        }
        if (!($refl =& self::$propertiesRefl[$class][$propertyName])) {
            $getter = self::getter($class, $propertyName);
            $refl = new \ReflectionMethod($class, $getter);
            self::$propertiesRefl[$class][$propertyName] = $refl;
        }
        // todo: smarter regexp
        if (!preg_match_all('~\\@([^\\s@\\(]+)[\\t ]*(?:\\(?([^\\n@]+)\\)?)?~i', $refl->getDocComment(), $annots, PREG_PATTERN_ORDER)) {
            return null;
        }
        foreach ($annots[1] as $i => $annot) {
            $annotations[strtolower($annot)] = empty($annots[2][$i]) ? true : rtrim($annots[2][$i], " \t\n\r)");
        }
        return $annotations;
    }