title: What does this error means in JSP? (Unknown element (rtexpvalue) in attribute)
body: <p>I am getting this error when running my application on LINE 3 of the jsp file.Is it to do with my tld file or jsp file?</p>
  
  <p>org.apache.jasper.JasperException: /DisplayAllOrders.jsp(3,62) PWC6106: Unknown element (rtexpvalue) in attribute.</p>
  
  <p>The TLD file:</p>
  
  <pre><code> &lt;?xml version="1.0" encoding="UTF-8"?&gt;
   &lt;taglib version="2.0" xmlns="http://java.sun.com/xml/ns/j2ee"    lns:xsi="http://www.w3.org/2001/XMLSchema-instance"      xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee web-jsptaglibrary_2_0.xsd"&gt;
   &lt;tlib-version&gt;1.0&lt;/tlib-version&gt;
   &lt;short-name&gt;week07_portfolio&lt;/short-name&gt;
   &lt;uri&gt;/WEB-INF/tlds/week07_portfolio&lt;/uri&gt;
  &lt;tag&gt;
  &lt;name&gt;DisplayOrders&lt;/name&gt;
  &lt;tag-class&gt;tags.DisplayOrders&lt;/tag-class&gt;
  &lt;body-content&gt;JSP&lt;/body-content&gt;
  &lt;variable&gt;
      &lt;name-given&gt;order&lt;/name-given&gt;
      &lt;variable-class&gt;beans.Order&lt;/variable-class&gt;
      &lt;declare&gt;true&lt;/declare&gt;
      &lt;scope&gt;NESTED&lt;/scope&gt;
  &lt;/variable&gt;       
  &lt;attribute&gt;
        &lt;name&gt;ordersListName&lt;/name&gt;
        &lt;required&gt;true&lt;/required&gt;
        &lt;rtexpvalue&gt;false&lt;/rtexpvalue&gt;
  &lt;/attribute&gt;
     &lt;/tag&gt;
     &lt;tag&gt;
     &lt;name&gt;DisplayOrderLines&lt;/name&gt;
     &lt;tag-class&gt;tags.DisplayOrderLines&lt;/tag-class&gt;
     &lt;body-content&gt;JSP&lt;/body-content&gt;
  &lt;variable&gt;
      &lt;name-given&gt;orderLine&lt;/name-given&gt;
      &lt;variable-class&gt;beans.OrderLine&lt;/variable-class&gt;
      &lt;declare&gt;true&lt;/declare&gt;
      &lt;scope&gt;NESTED&lt;/scope&gt;
  &lt;/variable&gt;     
   &lt;attribute&gt;
        &lt;name&gt;linesListName&lt;/name&gt;
        &lt;required&gt;true&lt;/required&gt;
        &lt;rtexpvalue&gt;false&lt;/rtexpvalue&gt;
    &lt;/attribute&gt;    
    &lt;/tag&gt;
   &lt;/taglib&gt;
  </code></pre>
  
  <p>the JSP file:</p>
  
  <pre><code>&lt;%@page contentType="text/html" pageEncoding="UTF-8"%&gt;
  &lt;%@ page import="java.util.*, java.text.*, beans.*" %&gt;
  &lt;%@ taglib uri="/WEB-INF/tlds/week07_portfolio" prefix="wk07" %&gt;
  &lt;!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
  "http://www.w3.org/TR/html4/loose.dtd"&gt;
  
  &lt;%  if (session.getAttribute("orderList") == null)
  {
      throw new ServletException("No order list available");
  }
  
  int ctr = 0;
  SimpleDateFormat df = new SimpleDateFormat("dd-MMM-yyyy");
  </code></pre>
  
  <p>%></p>
  
  <pre><code>&lt;html&gt;
  &lt;head&gt;
      &lt;meta http-equiv="Content-Type" content="text/html; charset=UTF-8"&gt;
      &lt;title&gt;Week 07, Portfolio Exercise&lt;/title&gt;
      &lt;link rel="stylesheet" type="text/css" href="Week07_Portfolio.css"&gt;
      &lt;/head&gt;
      &lt;body&gt;
      &lt;h1&gt;Week 07, Portfolio Exercise&lt;/h1&gt;
      &lt;h2&gt;Order list&lt;/h2&gt;
  
      &lt;wk07:DisplayOrders ordersListName="orderList"&gt;
          &lt;table&gt;
              &lt;tr class="header"&gt;
                  &lt;td&gt;Order Num: &lt;%= order.getOrderNum() %&gt;&lt;/td&gt;
                  &lt;td&gt;Customer: &lt;%= order.getName() %&gt;&lt;/td&gt;
                  &lt;td&gt;Date: &lt;%= df.format(order.getOrderDate()) %&gt;&lt;/td&gt;
              &lt;/tr&gt;
          &lt;/table&gt;
  
          &lt;% pageContext.setAttribute("orderLines", order.getOrderLines()); 
             ctr = 0;
          %&gt;
          &lt;table&gt;
              &lt;tr&gt;
                  &lt;th&gt;Ref. Code&lt;/th&gt;
                  &lt;th&gt;Item&lt;/th&gt;
                  &lt;th&gt;Qty&lt;/th&gt;
              &lt;/tr&gt;
          &lt;wk07:DisplayOrderLines linesListName="orderLines"&gt;
              &lt;tr&lt;%= ctr++ % 2 == 0 ? " class=\"shaded\"" : ""%&gt;&gt;
                  &lt;td&gt;&lt;%= orderLine.getItem().getRefCode()%&gt;&lt;/td&gt;
                  &lt;td&gt;&lt;%= orderLine.getItem().getName()%&gt;&lt;/td&gt;
                  &lt;td&gt;&lt;%= orderLine.getQuantity()%&gt;&lt;/td&gt;
              &lt;/tr&gt;
          &lt;/wk07:DisplayOrderLines&gt;
          &lt;/table&gt;
          &lt;p&gt;&amp;nbsp;&lt;/p&gt;
      &lt;/wk07:DisplayOrders&gt;        
  &lt;/body&gt;
  </code></pre>
  
  <p></p>