According to TLD or attribute directive in Tag file appears in JSP

According to TLD or attribute directive in Tag file appears in JSP, attribute value does not accept any expressions

A JSP exception occurs during application deployment and running. When jstl library is used: According to TLD or attribute directive in Tag file, attribute value does not accept any expressions, it may be because the jsp2.0 version is used, and the standby version of The jstl core library (RT Library) is not used. There are two solutions: 1. modify web. xml. <Web-app xmlns = "http://java.sun.com/xml/ns/j2ee" xmlns: xsi = "http://www.w3.org/2001/XMLSchema-instance" xsi: schemalocation = "http://java.sun.com/xml/ns/j2ee http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd" version = "2.4"> Changed to Version 2.3 <! Doctype web-app public "-// Sun Microsystems, Inc. // DTD web application 2.3 //" http://java.sun.com/dtd/web-app_2_3.dtd "> <Web-app> 2. Use the jstl core RT Library The jstl core library has two types of taglib pseudocommands. The Rt library relies on the traditional jsp request-time attribute value instead of El for implementation (called El library. jsp2.0 will support El) JSP using <% @ taglib uri = http://java.sun.com/jstl/core prefix = "C" %> in Version 2.3 can be, in version 2.4 will not work, is it version incompatible? As long <% @ Taglib uri = "http://java.sun.com/jstl/core" prefix = "C" %> Change <% @ Taglib uri = http://java.sun.com/jstl/core_rt prefix = "C" %>