Problem when report generation and JSF navigation

[Thomas Gaudin]

Hi,

I am using JasperReport to generate PDF files "on the fly".
It is working fine the first time I click on the link to the report but it fails alternatively every 2 clicks exactly...
I guess I am somehow messing up the navigation mecanism but I don't know where to start my investigation.
Any hint is warmly welcome.
Thanks,

Thomas

Here is the code :
--------------------
JSF Bean :
public class Reports extends BasePage implements Serializable {
    public String users() {      
        List results = userManager.getUsers(null);
        Map parameters = new HashMap();
        parameters.put("format", "pdf");
        parameters.put("WEBDIR", getServletContext().getRealPath("/"));
        try{
            InputStream is = getServletContext().getResourceAsStream("/WEB-INF/reports/userList.jrxml");
            JRBeanCollectionDataSource ds = new JRBeanCollectionDataSource(results);
           
            getResponse().setContentType("application/pdf");
            getResponse().addHeader("Content-Disposition", "attachment; filename=userList.pdf");
           
            JasperDesign jasperDesign = JRXmlLoader.load(is);
            JasperReport jasperReport = JasperCompileManager.compileReport(jasperDesign);
            JasperPrint jasperPrint = JasperFillManager.fillReport (jasperReport, parameters, ds);          
            JasperExportManager.exportReportToPdfStream(jasperPrint, getResponse().getOutputStream());

            getFacesContext().responseComplete();
        }
        catch(Exception e){
            log.error(e);
        }
        return null;
    }
--------------------
The link to generate report :
<h:commandLink value="report" action="" reports.users}"/>
--------------------
faces-config.xml :
     <managed-bean>
        <managed-bean-name>reports</managed-bean-name>
        <managed-bean-class>org.appfuse.webapp.action.Reports</managed-bean-class>
        <managed-bean-scope>request</managed-bean-scope>
        <managed-property>
            <property-name>userManager</property-name>
            <value>#{userManager}</value>
        </managed-property>
    </managed-bean>
--------------------