title: Displaytag export option is not working
body: <p>I am using Displaytag framework for pagination &amp; exporting purpose. In that i am also using Strut2Tiles Integration.</p>
  
  <p>Whenever i am calling any action class it will returning me a list &amp; through Displaytag i am successfully displaying record on my page. For that my jsp page's code looks like :</p>
  
  <pre><code>  &lt;s:set name="selectedPageSize" value="selectedPageSize" scope="request"/&gt;
          &lt;s:set value="accountList" scope="request" name="accountList"/&gt;
              &lt;display:table name="accountList" export="true" class="table" requestURI="" id="accountList" pagesize="${selectedPageSize}" &gt;
              &lt;display:setProperty name="export.pdf" value="true" /&gt; 
              &lt;display:column property="id" sortable="true" class="sort-title"/&gt;
              &lt;display:column property="name" sortable="true"/&gt;
              &lt;display:column property="contactPerson" sortable="true"/&gt;
              &lt;display:column property="phone1" sortable="true"/&gt;
              &lt;display:column property="phone2" sortable="true"/&gt;
              &lt;display:column property="fax" sortable="true"/&gt;
              &lt;display:column property="email" sortable="true"/&gt;
              &lt;display:column property="webSite" sortable="true"/&gt;
              &lt;display:column property="address1" sortable="true"/&gt;
              &lt;display:column property="address2" sortable="true"/&gt;
              &lt;display:column property="countryId.name" title="Country" sortable="true"/&gt;
              &lt;display:column property="stateId.name" title="State" sortable="true"/&gt;
              &lt;display:column property="countryId.name" title="City" sortable="true"/&gt;
  
              &lt;display:column property="isDeleted" sortable="true"/&gt;
  
              &lt;display:column title="Delete"&gt;
                  &lt;s:url id="removeUrl" action="finance/deleteAccount.action"&gt;
                      &lt;s:param name="id" value="#attr.accountList.id" /&gt;
                  &lt;/s:url&gt;
                  &lt;s:a href="%{removeUrl}" theme="ajax" targets="accountList"&gt;Remove&lt;/s:a&gt;
              &lt;/display:column&gt;
  
              &lt;display:column  title="Update"&gt;
                  &lt;s:url id="updateUrl" action="finance/updateAccount.action"&gt;
                      &lt;s:param  value="#attr.accountList.id" name="id"/&gt;
                  &lt;/s:url&gt;
                  &lt;s:a href="%{updateUrl}&amp;action=update" targets="accountlist"&gt;Update&lt;/s:a&gt;
              &lt;/display:column&gt;
  </code></pre>
  
  <p>Actually this page is displaying through tiles configuration.</p>
  
  <p>Here i have enabled the export option, so it is showing me the exporting options like CSV, EXCEL, XML. But whenver i am clicking on that CSV link, my web browser hanged, means nothing is displayed on it</p>
  
  <p>For that exporting solution i have also added filter in my web.xml. My web.xml looks like:</p>
  
  <pre><code>&lt;filter&gt;
      &lt;filter-name&gt;struts2&lt;/filter-name&gt;
      &lt;filter-class&gt;org.apache.struts2.dispatcher.FilterDispatcher&lt;/filter-class&gt;
  &lt;/filter&gt;
  
  &lt;filter-mapping&gt;
      &lt;filter-name&gt;struts2&lt;/filter-name&gt;
      &lt;url-pattern&gt;/*&lt;/url-pattern&gt;
  &lt;/filter-mapping&gt;
    &lt;filter&gt;
      &lt;filter-name&gt;ResponseOverrideFilter&lt;/filter-name&gt;
      &lt;filter-class&gt;org.displaytag.filter.ResponseOverrideFilter&lt;/filter-class&gt;
  &lt;/filter&gt;
  
  &lt;filter-mapping&gt;
      &lt;filter-name&gt;ResponseOverrideFilter&lt;/filter-name&gt;
      &lt;url-pattern&gt;*.action&lt;/url-pattern&gt;
  &lt;/filter-mapping&gt;
  &lt;filter-mapping&gt;
      &lt;filter-name&gt;ResponseOverrideFilter&lt;/filter-name&gt;
      &lt;url-pattern&gt;*.jsp&lt;/url-pattern&gt;
  &lt;/filter-mapping&gt;
  
  &lt;listener&gt;
      &lt;listener-class&gt;org.apache.struts2.tiles.StrutsTilesListener&lt;/listener-class&gt;
  &lt;/listener&gt;
  &lt;listener&gt;
      &lt;listener-class&gt;org.springframework.web.context.ContextLoaderListener&lt;/listener-class&gt;
  &lt;/listener&gt;
  
  &lt;context-param&gt;
      &lt;param-name&gt;contextConfigLocation&lt;/param-name&gt;
      &lt;param-value&gt;/WEB-INF/classes/webApplicationContext.xml&lt;/param-value&gt;
  &lt;/context-param&gt;
  
  &lt;welcome-file-list&gt;
      &lt;welcome-file&gt;jsp/welcome.jsp&lt;/welcome-file&gt;
  &lt;/welcome-file-list&gt;
  </code></pre>
  
  <p></p>
  
  <p>I have also included following list of libraries of displaytag :
  1) displaytag-1.2.jar
  2) displaytag-export-poi-1.2.jar
  3) displaytag-portlet-1.2.jar</p>
  
  <p>The exception that i am getting is :</p>
  
  <pre><code>2009-05-09 12:02:38,234 DEBUG (org.displaytag.tags.TableTag:1524) - Exportfilter NOT enabled
  2009-05-09 12:02:38,312  WARN (org.displaytag.tags.TableTag:63) - Exception: [.TableTag] Unable to reset response before returning exported data. You are not using an export filter. Be sure that no other jsp tags are used before display:table or refer to the displaytag documentation on how to configure the export filter (requires j2ee 1.3).
  ApplicationDispatcher[/PaginationTry2] PWC1231: Servlet.service() for servlet jsp threw exception
  Exception: [.TableTag] Unable to reset response before returning exported data. You are not using an export filter. Be sure that no other jsp tags are used before display:table or refer to the displaytag documentation on how to configure the export filter (requires j2ee 1.3).
  </code></pre>
  
  <p>Plz reply, i am stuck with this problem.</p>