Problem with empty report

[2005 IR Help]

By: Michael Bauer - mbabauer

Problem with empty report

2004-06-15 13:00

I am working on a web reporting engine using JasperReports as the processing piece, but I am having a problem with my JasperPrint object not returning any results.

 

My first iteration worked, but was clunky, so I moved it to STRUTS/JBoss. I now have a helper class that has a method that gets the HTML from the report. This code builds the JasperPrint as such:

 

JasperPrint print = null

String xml = <pull XML from Database>

StringInputStream sis = StringInputStream(xml);

JasperReport report = JasperManager.compileReportsis();

 

... do some stuff to build parameters Map...

 

Connection conn = null

... try to get the connection using JNDI, else just build it from the DB Drivers...

 

print = JasperManager.fillReport(report,map,conn);

 

 

I removed a bunch of the code, not because its super-secret, but because it was irrelevant really.

 

Anyway, later in the code I do:

JRHtmlExporter exporter = new JRHtmlExporter();

Boolean isOutImagesToDir = (Boolean)getProperty("jasper.report.image.output_to_dir",Boolean.FALSE);

exporter.setParameter(JRHtmlExporterParameter.IS_OUTPUT_IMAGES_TO_DIR,isOutImagesToDir);

if(isOutImagesToDir.booleanValue()) {

String outputDir = (String)getProperty("jasper.report.image.output_dir",".");

exporter.setParameter(JRHtmlExporterParameter.IMAGES_DIR_NAME,outputDir);

}

String imagesUri=(String)getProperty("jasper.report.images.uri");

if(imagesUri!=null && !imagesUri.equals("")) {

exporter.setParameter(JRHtmlExporterParameter.IMAGES_URI,imagesUri);

}

 

exporter.setParameter(JRHtmlExporterParameter.JASPER_PRINT,print);

exporter.setParameter(JRHtmlExporterParameter.OUTPUT_STRING_BUFFER,sBuff);

 

 

When the report prints, however, all I get is an empty web page, with the html and body tags, but no data or images. I tried exporting to a PDF file, but still I get an empty page. Up until the point that I create the JasperPrint, everything seems right in my debugger. Even the JasperReport object has elements and fields.

 

I have triple-checked my SQL and all seems fine. Whats wierd is that I had this working in a proof of concept.

 

One more question...does anyone know how to turn on logging or error reporting in JasperReports? Is it Log4J friendly? I would like to trace the code if I could.

 

 

Thanks in advance