PDFBox 2.0.7 无法设置 XFA答案

【问题标题】：PDFBox 2.0.7 Unable to set XFAPDFBox 2.0.7 无法设置 XFA
【发布时间】：2018-04-09 10:04:28
【问题描述】：

我正在尝试在具有动态输入字段的 pdf 表单中设置值，但我不断收到流编写器错误。

我研究了填写表格的步骤 (http://mail-archives.apache.org/mod_mbox/pdfbox-users/201510.mbox/browser) 并阅读了类似的问题 Combining XFA with PDFBox 和 PDFBox bloated PDF file size

有不同的方法吗？有什么提示可以引导我朝着正确的方向前进吗？

这是我的代码

PDDocument doc = null;
FileOutputStream fos = null;
COSStream cosout = null;

try {
    doc = PDDocument.load(new File(pdfTemplatePath));
    doc.setAllSecurityToBeRemoved(true);

    PDDocumentCatalog cat = doc.getDocumentCatalog();
    PDAcroForm aform = cat.getAcroForm();

    if (aform.hasXFA()) {

        PDXFAResource xfa = aform.getXFA();
        org.w3c.dom.Document xmlDoc = xfa.getDocument();

        Node xfaData = xmlDoc.getElementsByTagName("xfa:data").item(0);
        HashMap<String, String> xmlFields = new HashMap<String, String>();

        setDataElements(xfaData, xmlFields); //I set node contents here
        //System.out.println(xmlFields);

        cosout = new COSStream(new ScratchFile(new File("C://tests//")));

        TransformerFactory.newInstance().newTransformer()
                .transform(new DOMSource(xmlDoc), new StreamResult(cosout.createOutputStream()));

        PDXFAResource resout = new PDXFAResource(cosout);

        aform.setXFA(resout);

    }

    fos = new FileOutputStream(tempFilePath);

    doc.save(fos);
    doc.close();

} catch (Exception e) {
    e.printStackTrace();
    success = false;
} catch (Error err) {
    err.printStackTrace();
    success = false;
} finally {
    if (doc != null)
        doc.close();
    if (fos != null)
        fos.close();
    if (cosout != null)
        cosout.close();
}

这是我得到的错误

*java.lang.IllegalStateException: Cannot read while there is an open stream writer
        at org.apache.pdfbox.cos.COSStream.createRawInputStream(COSStream.java:133)
        at org.apache.pdfbox.pdfwriter.COSWriter.visitFromStream(COSWriter.java:1203)
        at org.apache.pdfbox.cos.COSStream.accept(COSStream.java:388)
        at org.apache.pdfbox.pdfwriter.COSWriter.doWriteObject(COSWriter.java:522)
        at org.apache.pdfbox.pdfwriter.COSWriter.doWriteObjects(COSWriter.java:460)
        at org.apache.pdfbox.pdfwriter.COSWriter.doWriteBody(COSWriter.java:444)
        at org.apache.pdfbox.pdfwriter.COSWriter.visitFromDocument(COSWriter.java:1099)
        at org.apache.pdfbox.cos.COSDocument.accept(COSDocument.java:419)
        at org.apache.pdfbox.pdfwriter.COSWriter.write(COSWriter.java:1370)
        at org.apache.pdfbox.pdfwriter.COSWriter.write(COSWriter.java:1257)
        at org.apache.pdfbox.pdmodel.PDDocument.save(PDDocument.java:1278)*

我尝试在保存文档之前关闭流（我没有看到有人在我阅读的示例中这样做），但随后又出现了另一个错误

*java.io.IOException: COSStream has been closed and cannot be read. Perhaps its enclosing PDDocument has been closed?
        at org.apache.pdfbox.cos.COSStream.checkClosed(COSStream.java:82)
        at org.apache.pdfbox.cos.COSStream.createRawInputStream(COSStream.java:130)
        at org.apache.pdfbox.pdfwriter.COSWriter.visitFromStream(COSWriter.java:1203)
        at org.apache.pdfbox.cos.COSStream.accept(COSStream.java:388)
        at org.apache.pdfbox.pdfwriter.COSWriter.doWriteObject(COSWriter.java:522)
        at org.apache.pdfbox.pdfwriter.COSWriter.doWriteObjects(COSWriter.java:460)
        at org.apache.pdfbox.pdfwriter.COSWriter.doWriteBody(COSWriter.java:444)
        at org.apache.pdfbox.pdfwriter.COSWriter.visitFromDocument(COSWriter.java:1099)
        at org.apache.pdfbox.cos.COSDocument.accept(COSDocument.java:419)
        at org.apache.pdfbox.pdfwriter.COSWriter.write(COSWriter.java:1370)
        at org.apache.pdfbox.pdfwriter.COSWriter.write(COSWriter.java:1257)
        at org.apache.pdfbox.pdmodel.PDDocument.save(PDDocument.java:1278)*

非常感谢任何帮助

【问题讨论】：

我对 xfa 了解不多，但请尝试以下操作：1) 使用 document.getDocument().createCOSStream() 创建您的 COSStream，2) 完成后注意关闭您的 cosout.createOutputStream() 对象，3) 关闭 @ 987654329@ 完成或直接保存到文件中。
将转换结果写入File 或byte[] 等中间存储，然后将其读入COSStream，因为它可以打开写入或读取。

标签： java pdf pdfbox xfa

【解决方案1】：

我使用document.getDocument().createCOSStream() 解决了这个问题，正如Tilman Hausherr 建议的那样，并在设置 XFA 资源后关闭创建的输出流，代码如下所示

COSStream cs = doc.getDocument().createCOSStream();
OutputStream os = cs.createOutputStream();

Result outputTarget = new StreamResult(os);
Transformer t = TransformerFactory.newInstance().newTransformer();
t.transform(new DOMSource(xmlDoc), outputTarget);

PDXFAResource resout = new PDXFAResource(cs);

aform.setXFA(resout);
os.close();
doc.save( "test.pdf" );

【讨论】：