List<String> list = new ArrayList<>();
    list.add("qwe");
    JRBeanCollectionDataSource beanCollectionDataSource = new JRBeanCollectionDataSource(list);

    InputStream reportPath =
            getClass().getClassLoader().getResourceAsStream("Bill.jasper");
    JasperCompileManager.compileReport(reportPath);
    jasperPrint = JasperFillManager.fillReport(reportPath, new HashMap(), beanCollectionDataSource);
    byte[] output = JasperExportManager.exportReportToPdf(jasperPrint);
    return output;