“JSF将输出视图层HTML和JavaScript，如果不进入控制器代码，您就无法控制或更改它们。”

实际上，JSF为您提供了灵活性，您既可以使用标准/第三方组件，也可以创建自己的组件，您可以完全控制呈现的内容。使用JSF 2.0创建自定义组件只需要一个xhtml。

Inexperienced developers usually will create applications that are painfully slow and code will be really ugly and hard to maintain. Its deceptively simple to start, but actually requires some investment in learning if you want to write good programs. At least at the start you will often "stuck" on some problem and will spend more time reading balusc posts on internet than actually working :) After a while it will be less and less of that, but it still can be annoying. Even more annoying when you find out that the problem is not due to you lack of knowledge/mistake but actually a bug. Mojarra was(is?) quite buggy, and another layer of components adds even more problems. Richfaces was biggest piece of crap software ever written :) Don't know how it is now on version 4. We have Primefaces which is better, but still you will run into bugs or lack of features especially with more exotic components. And now you will need to pay for Primefaces updates. So I would say its buggy but its getting better especially after 2.2 version fixed some problems with spec. Framework getting more mature but still far from perfect (maybe myfaces better?). I don't find it especially flexible. Often if you need something very very customized and there are no components that does that - it will be a bit painful. Again I'm talking from average developer perspective - the one with deadlines, quick reading tutorials, and searching stackoverflow when getting stuck because no time to learn how it really works :) Often some components seems to have "almost" what you need, but not exactly and sometimes you might spend too much time to make it do something you want :) Need to be careful in evaluating if its better to create your own or torture existing component. Actually if you are creating something really unique I would not recommend JSF.

简而言之，我的缺点是:复杂，开发过程不流畅，漏洞百出，缺乏灵活性。

当然也有好处，但这不是你问的。不管怎样，这是我使用框架的经验，其他人可能有不同的意见，所以最好的方法是尝试一段时间，看看它是否适合你(只是一些更复杂的东西-不是天真的例子- JSF真的很出色:)依我看，JSF的最佳用例是业务应用程序，如crm等…

我们使用JSF开发了一个示例项目(这是一个为期三周的研究，所以我们可能会丢失一些东西!)

我们尝试使用核心jsf，如果需要组件，我们使用PrimeFaces。

该项目是一个带有导航功能的网站。当点击菜单时，每个页面都应该通过ajax加载。

该网站有两个用例:

带有网格的页面。网格是通过ajax加载的，应该支持排序和分页 一个三步向导页面。每个页面都有客户端验证(用于简单验证)和服务器端ajax基础验证(用于复杂验证)。任何服务器异常(来自服务层)应该显示在向导的同一页上，而不需要导航到下一页。

我们发现:

You need to use some hacks from omniFaces to make the JSF view state fixed. The JSF state will be corrupted when you include pages via ajax in each other. This seems a bug in JSF and may be fixed on next releases (not in 2.3). The JSF Flow is not working correctly with ajax (or we could not make it work!) We try to use primeface wizard component instead but the client validation seems not supported and mean while it was not standard JSF flow standard. When using some jQuery components like jqGird, and you need to load JSON results, then you are advised to use pure servlet, The JSF will do nothing for you. So if you use these kind of components, your design will not fit in JSF. We try to do some client scripts when ajax complete by ajaxComplete and we found that the PF 4 has implemented its own ajax events. We had some jQuery components and we need to change their code.

如果您将上面的示例更改为非Ajax项目(或至少是较少的Ajax项目)，您将不会面临上述许多问题。

我们将我们的研究总结为:

JSF在一个完全基于ajax的网站上不能很好地工作。

当然，我们发现JSF中有很多不错的特性，这些特性在某些项目中可能非常有用，所以请考虑您的项目需求。

请参考JSF技术文档来回顾JSF的优点，在我看来JSF最大的优点是来自@BalusC的完全和巨大的支持;-)

JSF有很多优点，关于缺点的问题，让我再补充一点。

在实现一个web项目的实际场景中，在一个时间框架内，你需要注意以下因素。

你的团队中是否有足够多的资深成员提出最好的建议 适合每个场景的控件? 你有足够的带宽来适应最初的学习曲线吗? 您的团队中是否有足够的专家来审查JSF 开发者制作的东西?

如果你对这些问题的回答是“不”，你可能会在不可维护的代码库中结束。

对我来说，JSF 2.0最大的缺点不仅是JSF的学习曲线，而且是为了让它做有用的工作而必须使用的组件库。想想你要真正精通需要处理的数量惊人的规范和标准:

HTML in the various incarnations. Don't pretend you don't need to know it. HTTP -- when you can't figure out what is going on you have to open Firebug and see. For that you need to know this. CSS -- Like it or not. It isn't so bad really and there are some nice tools out there at least. XML -- JSF will probably the first place you use namespaces to this degree. Servlet Specification. Sooner or later you will get into calling methods in this package. Aside from that you have to know how your Facelets gets turned into XHTML or whatever. JSP (mostly so you know why you don't need it in JSF) JSTL (again, mostly to cope with legacy framework) Expression Language (EL) in its various forms. ECMAScript, JavaScript, or whatever else you want to call it. JSON -- you should know this even if you don't use it. AJAX. I would say JSF 2.0 does a decent job of hiding this from you but you still need to know what is going on. The DOM. And how a browser uses it. See ECMAScript. DOM Events -- a topic all by itself. Java Persistence Architecture (JPA) that is if you want your app to have any back end data base. Java itself. JSEE while you are at it. The Context Dependency Injection specification (CDI) and how it clashes with and is used with JSF 2.0 JQuery -- I would like to see you get along without it.

现在，一旦你完成了这些，你就可以继续使用专有规范，即你将在此过程中获得的组件库和提供者库:

PrimeFaces(我选择的组件库) RichFaces MyFaces ICEFaces EclipseLink(我的JPA提供者) Hibernate 焊接

别忘了容器!所有这些配置文件:

GlassFish(2,3等) JBoss Tomcat

那么——这让事情变得简单了吗?当然，JSF 2.0很“简单”，只要你想做的只是最基本的web页面和最简单的交互。

简单地说，JSF 2.0是当今软件界所存在的最复杂和最麻烦的技术大杂烩。我想不出还有什么更好的方法。

JSF只有一个缺点:在开始“JSF”开发之前，你应该清楚地了解web开发、核心java和前端架构。

现在“新的”JavaScript框架只是试图复制/粘贴“JSF”基于组件的模型。