jstl length
<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %>
<%@ taglib uri="http://java.sun.com/jsp/jstl/functions" prefix="fn" %>
<html>
<head>
<title>JSTL fn:length() example</title>
</head>
<body>
<c:set var="str1" value="This is first string"/>
<c:set var="str2" value="Hello"/>
Length of the String-1 is: ${fn:length(str1)}<br>
Length of the String-2 is: ${fn:length(str2)}
</body>
</html>