java - EL expression for class -

i don't understand how represent class in el expressions.

i have el function takes class parameter (namely enum class) return possible enum values.

i want invoke el expression. e.g. ${mytld:enumer(com.example.enums.myenum)}

however:

• the above syntax passes null argument
• using myenum.class throws exception such expression cannot evaluated

how express class in el without possibly passing string representation?

the below works

<function>     <description>         returns list of enum values given enum class     </description>     <name>enumer</name>     <function-class>com.example.functions</function-class>     <function-signature>list enumer(java.lang.string)</function-signature> </function>  ${tld:enumer('com.example.myenum')} 

what like

    <function-signature>list enumer(java.lang.class)</function-signature> 

you can't represent class in plain el. can @ pass through if bean property ${mytld:enumer(bean.someenumclass)} returning class<? extends enum>, or ${mytld:enumer(bean.someenum['class'])} someenum actual enum, that's it. passing around class name string best bet.

if you're on el 3.0 (available on servlet 3.1 containers tomcat 8, wildfly 8, etc), alternative custom function import right away in jsp below using new el 3.0 importhandler api:

${pagecontext.elcontext.importhandler.importclass('com.example.enums.myenum')} 

the enum available ${myenum}.

<c:foreach items="${myenum.values()}" var="myenumvalue">     ${myenumvalue}<br/> </c:foreach> 

alternatively, import ${myenum} globally via servlet context listener below:

@weblistener public class config implements servletcontextlistener {      @override     public void contextinitialized(servletcontextevent event) {         jspfactory.getdefaultfactory().getjspapplicationcontext(event.getservletcontext()).addelcontextlistener(new elcontextlistener() {             @override             public void contextcreated(elcontextevent event) {                 event.getelcontext().getimporthandler().importclass(myenum.class.getname());             }         });     }      // ... }