Check a collection size with JSTL

Question

How can i check the size of a collection with JSTL?

Something like:

<c:if test="${companies.size() > 0">

</c:if>

Answer 1

from: http://java.sun.com/products/jsp/jstl/1.1/docs/tlddocs/fn/tld-summary.html

length( java.lang.Object) - Returns the number of items in a collection, or the number of characters in a string.

put this at the top of the page to allow the fn namespace

 <%@ taglib prefix="fn" uri="http://java.sun.com/jsp/jstl/functions" %>

and use like this in your jsp page

<p>The length of the companies collection is : ${fn:length(companies)}</p>

(from memory)

So to test with length of a collection:

<c:if test="${fn:length(companies) gt 0}">
   <p>It is greater than 0</p>
</c:if>

Note the use of gt instead of > as > is not allowed inside jsp/jsf tags.