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public static void main(String[] args) throws Throwable {
 
        JasperReport jasperReport;
        JasperPrint jasperPrint;
        Map<String, Object> parameter = new HashMap<String, Object>();
 
        parameter.put("aParameter", "hallo");
 
        try {
            jasperReport = JasperCompileManager
                    .compileReport("C:/Users/CKaus/Desktop/helloworld.jrxml");
 
            jasperPrint = JasperFillManager.fillReport(jasperReport, parameter);
            JasperExportManager.exportReportToPdfFile(jasperPrint,
                    "C:/Users/CKaus/Desktop/helloworld.pdf");
 
        } catch (JRException e) {
            e.printStackTrace();
        }
    }