ZK wraps RenderRequest to org.zkoss.web.portlet.RenderHttpServletRequest and RenderResponse to org.zkoss.web.portlet.RenderHttpServletResponse, using static getInstance() methods.

It causes exceptions that go like this :

13:56:15,342 ERROR [com.liferay.portal.kernel.servlet.PortletServlet] (http--0.0.0.0-8080-2) javax.portlet.PortletException: javax.servlet.ServletException: Original SevletRequest or wrapped original ServletRequest not passed to RequestDispatcher in violation of SRV.8.2 and SRV.14.2.5.1: javax.portlet.PortletException: javax.servlet.ServletException: Original SevletRequest or wrapped original ServletRequest not passed to RequestDispatcher in violation of SRV.8.2 and SRV.14.2.5.1
>> at org.zkoss.web.portlet.ServletPortletDispatcher.include(ServletPortletDispatcher.java:57) [zweb-6.0.0.jar:]
>> at org.zkoss.web.portlet.Portlets.include(Portlets.java:72) [zweb-6.0.0.jar:]
>> at org.zkoss.zk.ui.http.DHtmlLayoutPortlet.handleError(DHtmlLayoutPortlet.java:335) [zk-6.0.0.jar:6.0.0]
>> at org.zkoss.zk.ui.http.DHtmlLayoutPortlet.doView(DHtmlLayoutPortlet.java:146) [zk-6.0.0.jar:6.0.0]

JBoss & Tomcat (when using Liferay 6.1) are affected. If we try not to use strict servlet compliance (by setting system property "-Dorg.apache.catalina.STRICT_SERVLET_COMPLIANCE=false"), this leads to another exception wich is shown below :

14:16:58,743 ERROR [portal-web.docroot.html.portal.render_portlet_jsp] (http--0.0.0.0-8080-2) java.lang.ClassCastException: org.zkoss.web.portlet.RenderHttpServletRequest cannot be cast to javax.servlet.ServletRequestWrapper
>> at org.apache.catalina.core.ApplicationFilterFactory.createFilterChain(ApplicationFilterFactory.java:164)
>> at org.apache.catalina.core.ApplicationDispatcher.invoke(ApplicationDispatcher.java:827)
>> at org.apache.catalina.core.ApplicationDispatcher.doInclude(ApplicationDispatcher.java:720)
>> at org.apache.catalina.core.ApplicationDispatcher.include(ApplicationDispatcher.java:657)
>> at org.zkoss.web.portlet.ServletPortletDispatcher.include(ServletPortletDispatcher.java:51)
>> at org.zkoss.web.portlet.Portlets.include(Portlets.java:72)
>> at org.zkoss.zk.ui.http.DHtmlLayoutPortlet.handleError(DHtmlLayoutPortlet.java:335)
>> at org.zkoss.zk.ui.http.DHtmlLayoutPortlet.doView(DHtmlLayoutPortlet.java:146)

Workaround : As an alternative, I rewrote org.zkoss.web.portlet.RenderHttpServletRequest to use standard javax.servlet.http.HttpServletRequestWrapper. Here's my code :

/**

• A facade of RenderRequest that implements HttpServletRespose.
• @author tomyeh
  */
  public class RenderHttpServletRequest implements HttpServletRequest {
  private final RenderRequest _req;
  private final HttpServletRequest _hreq;
  private String _enc = "UTF-8";
  private final Map<String, String> _attrs = new HashMap<String, String>(8);

public static HttpServletRequest getInstance(RenderRequest req) {
final HttpServletRequest res;

if (req instanceof HttpServletRequest)

{ res = (HttpServletRequest) req; }

else

{ res = new RenderHttpServletRequest2(req); }

// wraps HttpServletRequest to prevent further type checks :
return new HttpServletRequestWrapper(res);
}

... code unchanged after that ...
}

As a better alternative, RenderHttpServletRequest & RenderHttpServletResponse should inherit from (resp.) HttpServletRequestWrapper & HttpServletResponseWrapper or at least, use such wrappers in getInstance() methods.