JSTL if-statement inside HTML-attribute

is it possible to do something like this in JSTL:

<div class="firstclass<c:if test='true'> someclass</c:if>">
   开发者_如何学编程<p>some other stuff...</p>
</div>

Is there any way to get this to work, or is there a better way to add a class by looking at a JSTL-if-statement?

It's also possible to use an EL expression directly like this:

<div class="${booleanExpr ? 'cssClass' : 'otherCssClass'}">
</div>

<c:if test='true'> 
  <c:set value="someclass" var="cssClass"></c:set>
</c:if> 
<div class="${cssClass}">
   <p>some other stuff...</p>
</div>

That works for me!

<div id="loginById" style="height:<% out.print(instanceClass.booleanMethod()? "250px": "150px");%>">