Integrating JasperReports

Hi there,
I've been trying for many days to integrate JasperReports into my Vaadin webapp, but without success, even if I followed similar forum threads answers. I always get a blank page without any report. I hope you can help me.

The code I used is this:

final Connection conn = helper.getJDBCConnectionPool().reserveConnection();
final HashMap map = new HashMap();

StreamResource.StreamSource source = new StreamResource.StreamSource() {
	@Override
	public InputStream getStream() {
		byte[] b = null;
		try {
			InputStream rep = getClass().getClassLoader().getResourceAsStream("reports/myreport.jasper");
			if (rep == null) {
				getWindow().showNotification("No report!");
            } else {
            	JasperReport report = (JasperReport) JRLoader.loadObject(rep);
                b = JasperRunManager.runReportToPdf(report, null, conn);
            }
		} catch (Exception ex) {
			ex.printStackTrace();
		}
		return new ByteArrayInputStream(b);
	}
};

StreamResource resource = new StreamResource(source, "report.pdf", getApplication());
resource.setMIMEType("application/pdf");
resource.setCacheTime(0);

getApplication().getMainWindow().open(resource, "_new");
conn.commit();
helper.getJDBCConnectionPool().releaseConnection(conn);

Another try I did is this:

JasperPrint print = JasperFillManager.fillReport(getClass().getClassLoader().getResourceAsStream("reports/myreport.jasper"), map, conn);
JRHtmlExporter exporter = new JRHtmlExporter();
final ByteArrayOutputStream output=new ByteArrayOutputStream();
exporter.setParameter(JRExporterParameter.JASPER_PRINT, print);
exporter.setParameter(JRExporterParameter.OUTPUT_STREAM,output);            
exporter.exportReport();
output.flush();

StreamResource.StreamSource source = new StreamResource.StreamSource() {
     
    public InputStream getStream() {
       byte[] b = null;
        b=output.toByteArray();
        return new ByteArrayInputStream(b);
    }
};

StreamResource resource = new StreamResource(source, "report.html", getApplication());
resource.setCacheTime(0);
getApplication().getMainWindow().open(resource, "_new");

conn.commit();
helper.getJDBCConnectionPool().releaseConnection(conn);

Please help! I did not find any solution yet...

How could I display jasper reports into a Vaadin web application? Using the above code I get a blank report. I tried embedding directly a pdf file, instead of generating a jasper report, and it's displayed blank too.

I hope anybody can help solving this. Thanks.

Please help! I did not find any solution to this problem... I'm not able to display an embebbed PDF, I always get a blank page, even if I try to embed directly a PDF document without jasper reports.

Have you tried setting the Content-Disposition?

resource.getStream().setParameter("Content-Disposition", "attachment;filename=\"" + namefile + "\"");
resource.setMIMEType("application/pdf");

(You can find more about it here: https://vaadin.com/forum/-/message_boards/view_message/452398 )