Jasper报告导出文件pdf空白？

Question

我使用库jasper报告导出文件pdf，结果是通过文件jrxml简单的hello world文件pdf空白。这是我的代码生成器PDF：

@Cachable

然后我使用oracle jdk进行检查：

@Override
public byte[] generatePDFReport(String inputFileName, Map<String, Object> params, JRDataSource dataSource) {
    byte[] bytes = null;
    JasperReport jasperReport = null;
    try (ByteArrayOutputStream byteArray = new ByteArrayOutputStream()) {
        // Check if a compiled report exists
        if (storageService.jasperFileExists(inputFileName)) {
            jasperReport = (JasperReport) JRLoader.loadObject(storageService.loadJasperFile(inputFileName));
        }
        // Compile report from source and save
        else {
            String jrxml = storageService.loadJrxmlFile(inputFileName);
            jasperReport = JasperCompileManager.compileReport(jrxml);
            // Save compiled report. Compiled report is loaded next time
            JRSaver.saveObject(jasperReport, storageService.loadJasperFile(inputFileName));
        }
        JasperPrint jasperPrint = JasperFillManager.fillReport(jasperReport, params, dataSource);
        // return the PDF in bytes
        bytes = JasperExportManager.exportReportToPdf(jasperPrint);
    } catch (JRException | IOException e) {
        log.error("Encountered error when loading jasper file", e);
    }
    return bytes;
}
@Override
public byte[] generatePDFReport(String inputFileName, Map<String, Object> params) {
    return generatePDFReport(inputFileName, params, new JREmptyDataSource());
}

您能告诉我问题以及如何解决吗？