title: How to create a custom EL function to invoke a static method?
body: <p>Im new to JSF 2. My question is related to BalusC's answer to this question <a href="https://stackoverflow.com/q/5709381/614130">jsf2 ajax update parts based on request parameters</a>  I tried the kickstart code BalusC posted and I encountered an EL parsing error:</p>
  
  <pre><code> /nameofpage.xhtml @12,64 rendered="#{bean.panels.contains('u1')}"
   Error Parsing: #{bean.panels.contains('u1')}
  </code></pre>
  
  <p>I guess that this is caused because I'm not running a Servlet 3.0 / EL 2.2 capable container with a /WEB-INF/web.xml declared as per Servlet 3.0 spec. I'm using Tomcat 6.</p>
  
  <p>BalusC suggested in his answer to create a custom EL function. But how do I accomplish this using a custom EL function?  Or can this be fixed by just configuring certain parts of my project?</p>
  
  <p>Below is my <code>web.xml</code>:</p>
  
  <pre><code>&lt;?xml version="1.0" encoding="UTF-8"?&gt;
  &lt;web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" version="2.5"&gt;
    &lt;servlet&gt;
      &lt;servlet-name&gt;Faces Servlet&lt;/servlet-name&gt;
      &lt;servlet-class&gt;javax.faces.webapp.FacesServlet&lt;/servlet-class&gt;
    &lt;/servlet&gt;
    &lt;servlet-mapping&gt;
      &lt;servlet-name&gt;Faces Servlet&lt;/servlet-name&gt;
      &lt;url-pattern&gt;*.jsf&lt;/url-pattern&gt;
    &lt;/servlet-mapping&gt;
    &lt;context-param&gt;
      &lt;param-name&gt;javax.faces.PROJECT_STAGE&lt;/param-name&gt;
      &lt;param-value&gt;Development&lt;/param-value&gt;    
    &lt;/context-param&gt;      
    &lt;welcome-file-list&gt;
      &lt;welcome-file&gt;index.jsp&lt;/welcome-file&gt;
      &lt;welcome-file&gt;index.html&lt;/welcome-file&gt;
    &lt;/welcome-file-list&gt;
  &lt;/web-app&gt;
  </code></pre>