Vaadin Jasper Report

public static void stampaReport(final String nomeFile, long p1) {
        String path = "/com/myapp/reports/";
        final String reportFile = path + nomeFile;
        final HashMap parameters = new HashMap();
        parameters.put("id", p1);

        try {
            StreamResource.StreamSource source = new StreamResource.StreamSource() {

                public InputStream getStream() {
                    byte[] b = null;
                    Connection conn = null;
                    try {
                        InputStream report = getClass().getClassLoader().getResourceAsStream(reportFile);
                        if (report == null) {
                            Notification.show("No report!", Type.ERROR_MESSAGE);
                            return null;
                        }
                        conn = getDbHelp().getJDBCConnectionPool().reserveConnection();
                        b = JasperRunManager.runReportToPdf(report, parameters, conn);
                        conn.commit();
                    } catch (Exception e) {
                        e.printStackTrace();
                    } finally {
                        getDbHelp().getJDBCConnectionPool().releaseConnection(conn);
                    }

                    return new ByteArrayInputStream(b);
                }
            };

            StreamResource resource = new StreamResource(source, "report.pdf");
            resource.getStream().setParameter("Content-Disposition", "attachment;filename=\"report.pdf\"");
            resource.setMIMEType("application/pdf");
            resource.setCacheTime(0);

            Window w = new Window();
            w.setModal(true);
            w.setCloseShortcut(KeyCode.ESCAPE, null);
            w.setResizable(false);
            //w.setClosable(false);
            w.setHeight(90.0f, Unit.PERCENTAGE);
            w.setWidth(90.0f, Unit.PERCENTAGE);

            BrowserFrame e = new BrowserFrame("Print", resource);
            e.setSizeFull();

            VerticalLayout layout = new VerticalLayout();
            layout.setSizeFull();
            layout.addComponent(e);

            w.setContent(layout);
            UI.getCurrent().addWindow(w);
            w.focus();
        } catch (Exception e) {
            e.printStackTrace();
            Notification.show("Error during report generation!", Type.ERROR_MESSAGE);
        }
    }