Showing string length in foreach

Question

I would like to show the length of each string inside the foreach loop. However, I get error with the following code. How can I do that? Thanks.
<%@ taglib uri="http://java.sun.com/jsp/jstl/core_rt" prefix="c" %>
<c:set var="strs" value="Peter, Paul, Mary" scope="page" />
<c:forEach var="str" items="${pageScope.strs}">
    <c:out value="${str.length()}"/>
</c:forEach>

Answer 1

EL is not Java.
EL can only access revealed properties of a bean. In most cases that corresponds to getter/setter methods declared in a bean.
That means you can't directly get the length of a string or the size of a collection.
They fixed this in JSTL1.1 by including a length function to do it for you.
You also seem to be using an incorrect import statement for your taglibrary. That uri is not any of those specified by the specifications. Most probably you want to use the standard URI for JSTL1.1
<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %>
<%@ taglib uri="http://java.sun.com/jsp/jstl/functions" prefix="fn" %>
<c:set var="strs" value="Peter, Paul, Mary" scope="page" />
<c:forEach var="str" items="${pageScope.strs}">
    <c:out value="${str} is ${fn:length(fn:trim(str))} characters long"/>
</c:forEach>Cheers,
evnafets