为什么 JRPrintServiceExporter 不适合 A4 页面？

Question

我们使用 jasper 进行报告。 在浏览器的预览模式下，它适合 A4 页面，但是，当它通过 JRPrintServiceExporter 打印时，它不适合 A4 页面。 我有以下代码：

public void printReport(Integer reportId, Date startDate, Date endDate, boolean isAutoPrint, String lang) {   
try {
        Map<String, Object> reportContent = getReportContent(reportId, startDate, endDate, isAutoPrint, lang);
        Collection<ReportDataItem> reportDataItems = (Collection<ReportDataItem>)
                reportContent.remove("datasource");
        Map<String, Object> params = reportContent;
        String jasperPath = "/jasper/jreport.jasper";
        JasperPrint jasperPrint = JasperFillManager.fillReport(getClass().getResourceAsStream(jasperPath), params,
                new JRBeanArrayDataSource(reportDataItems.toArray()));
        PrinterJob printerJob = PrinterJob.getPrinterJob();
        PageFormat pageFormat = PrinterJob.getPrinterJob().defaultPage();
        printerJob.defaultPage(pageFormat);

        PrintService printService = PrintServiceLookup.lookupDefaultPrintService();

        JRPrintServiceExporter exporter;
        PrintRequestAttributeSet printRequestAttributeSet = new HashPrintRequestAttributeSet();
        printRequestAttributeSet.add(MediaSizeName.ISO_A4);
        printRequestAttributeSet.add(new Copies(1));

        //TODO Replace obsolete calls
        exporter = new JRPrintServiceExporter();
        exporter.setParameter(JRExporterParameter.JASPER_PRINT, jasperPrint);
        exporter.setParameter(JRPrintServiceExporterParameter.PRINT_SERVICE, printService);
        exporter.setParameter(JRPrintServiceExporterParameter.PRINT_SERVICE_ATTRIBUTE_SET,
                printService.getAttributes());
        exporter.setParameter(JRPrintServiceExporterParameter.PRINT_REQUEST_ATTRIBUTE_SET,
                printRequestAttributeSet);
        exporter.setParameter(JRPrintServiceExporterParameter.DISPLAY_PAGE_DIALOG, Boolean.FALSE);
        exporter.setParameter(JRPrintServiceExporterParameter.DISPLAY_PRINT_DIALOG, Boolean.FALSE);
        exporter.exportReport();
    } catch (Exception ex) {
        throw new RuntimeException(ex);
    }

您可以找到通过浏览器预览打印打印的页面：

但这是通过上面代码中的 JRPrintServiceExporter 打印的，（请看左右两侧。抱歉图像模糊）：