未加星标

Creating Exception types on-the-fly in modern PHP - Matthew Weier O'Phinney

字体大小 | |
[开发(php) 所属分类 开发(php) | 发布者 店小二03 | 时间 2018 | 作者 红领巾 ] 0人收藏点击收藏

We pioneered a pattern for exception handling for Zend Framework back as we initially began development on version 2 around seven years ago. The pattern looks like this:

We would create a marker ExceptionInterface for each package. We would extend SPL exceptions and implement the package marker interface when doing so.

What this gave users was the ability to catch in three ways:

They could catch the most specific exception type by class name. They could catch all package-level exceptions using the marker interface. The could catch general exceptions using the associated SPL type.

So, as an example:

try { $do->something(); } catch (MostSpecificException $e) { } catch (PackageLevelExceptionInterface $e) { } catch (\RuntimeException $e) { }

This kind of granularity is really nice to work with. So nice that some standards produced byphp-FIG now ship them, such as PSR-11 , which ships a ContainerExceptionInterface and a NotFoundExceptionInterface .

One thing we've started doing recently as we make packages support only PHP 7 versions is to have the marker ExceptionInterface extend the Throwable interface; this ensures that implementations must be able to be thrown!

So, what happens when you're writing a one-off implementation of something that is expected to throw an exception matching one of these interfaces?

Why, use an anonymous class, of course!

As an example, I was writing up some documentation that illustrated a custom ContainerInterface implementation today, and realized I needed to throw an exception at one point, specifically a Psr\Container\NotFoundExceptionInterface . I wrote up the following snippet:

$message = sprintf(/* ... */); throw new class($message) extends RuntimeException implements NotFoundExceptionInterface { };

Done!

This works because RuntimeException takes a message as the first constructor argument; by extending that class, I gain that behavior. Since NotFoundExceptionInterface is a marker interface, I did not need to add any additional behavior, so this inline example works out-of-the-box.

What else are you using anonymous classes for?

Posted by Matthew Weier O'Phinney ,

本文开发(php)相关术语:php代码审计工具 php开发工程师 移动开发者大会 移动互联网开发 web开发工程师 软件开发流程 软件开发工程师

分页:12
转载请注明
本文标题:Creating Exception types on-the-fly in modern PHP - Matthew Weier O'Phinney
本站链接:https://www.codesec.net/view/620798.html


1.凡CodeSecTeam转载的文章,均出自其它媒体或其他官网介绍,目的在于传递更多的信息,并不代表本站赞同其观点和其真实性负责;
2.转载的文章仅代表原创作者观点,与本站无关。其原创性以及文中陈述文字和内容未经本站证实,本站对该文以及其中全部或者部分内容、文字的真实性、完整性、及时性,不作出任何保证或承若;
3.如本站转载稿涉及版权等问题,请作者及时联系本站,我们会及时处理。
登录后可拥有收藏文章、关注作者等权限...
技术大类 技术大类 | 开发(php) | 评论(0) | 阅读(9)