问题
I'm starting to work with JSF 2 so I wanted to give a try to h:outputStylesheet. It works fine but then I tried to apply the "pattern" or trick of adding a query string to the request which changes with the file version to force browsers to fetch changes.
Something like what is used here.
Unfortunately I haven't been able to do it. Actually, when using that tag it doesn't generate a simple URL but a computed one which already has a query string. I've found some info about versioning of resouces in JSF 2 both in the spec and here, but it seems to refer to multiple versions of a resource which is not what I need.
Of course I can always go back to NOT use the new tag. But I wanted to share this here for discussion.
Update 1 - some example:
What I've tried is something like this:
<h:outputStylesheet library="css" name="estilo.css?v=1" target="head"/>
Which renders as:
<link type="text/css" rel="stylesheet" href="RES_NOT_FOUND" />
Quite descriptive. ;-)
What I try to get is something like this:
<link rel="stylesheet" type="text/css" href="../css/estilo.css?v=1"/>
Which, using JSP, I used to put this way:
<link rel="stylesheet" type="text/css"
href="<c:url value='/css/estilo.css?v=${initParam.version}'/>"/>
回答1:
Facing the same challenge, I ended up extending javax.faces.application.ResourceHandlerWrapper and javax.faces.application.ResourceWrapper to append "&v=x.y.z" to the result of ResourceWrapper#getRequestString().
I saw this kind of solution implemented by Primefaces and Openfaces. Just take a look at the source of
org.primefaces.application.PrimeResourceHandler#createResource(String resourceName, String libraryName)
and
org.primefaces.application.PrimeResource#getRequestPath()
Available here.
Don't forget to add your implementation to faces-config.xml:
<application>
<resource-handler>your.package.YourResourceHandlerWrapper</resource-handler>
</application>
来源：https://stackoverflow.com/questions/4268345/how-can-i-implement-css-versioning-to-solve-cache-issues-using-jsf-2-houtpu