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<p:graphicImage value="#{resource['images:primefaces-ui/#{car.manufacturer}.jpg']}"/>

I would like to calculate the inner el first and then calculate the path using resource API. I tried <c:set> tag but its variable is also an EL, so it does not make any difference.

BalusC
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Ravi Kadaboina
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1 Answers1

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In the current EL 2.2 version, you cannot nest EL expressions nor String-concatenate EL variables that way. Use <c:set> to prepare the dynamic key before using it in another EL expression by simply inlining the EL expression in a string:

<c:set var="resourceName" value="images:primefaces-ui/#{car.manufacturer}.jpg" />
<p:graphicImage value="#{resource[resourceName]}"/>

An alternative is simply using library and name attributes instead of generating an URL based on those via #{resource} mapping:

<p:graphicImage library="images" name="primefaces-ui/#{car.manufacturer}.jpg" />

Update: since EL 3.0, you can use the += operator to String-concatenate EL variables, if you really can't use library/name for some reason.

<p:graphicImage value="#{resource['images:primefaces-ui/' += car.manufacturer += '.jpg']}"/>
BalusC
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  • This is relying on a ui:param implementation detail though - it does not promise to set variable in the current template context. I'll reference BalusC's own answer: http://stackoverflow.com/a/20376916/1341535 – Vsevolod Golovanov Aug 08 '14 at 17:23