php对象工厂类

 100) {
				$param_sign = md5($param_sign);
			}
			$class_sign = $class_name.'@'.$param_sign;
		}
		if (isset(self::$objSet[$class_sign])) {
			return self::$objSet[$class_sign];
		}
		$ref = new ReflectionClass($class_name);
		if ($ref->hasMethod('__construct') && !empty($params)) {
			$obj = $ref->newInstanceArgs($params);
		} else {
			$obj = $ref->newInstance();  
		}
		self::$objSet[$class_sign] = $obj;
		return $obj;
	}
}