java - PDFBox 2 不创建 PDF/A 文件

Question

我正在尝试使用 PDFBox 2 创建 PDF/A 文件。我的代码基于 exmpale 代码 here 。代码运行没有错误。但是，如果我使用 callas pdfPilot 和 veraPDF 验证文件，则没有 XMP 元数据，也没有 PDF/A 版本信息。 PDF 文件的版本也是 1.4。不是代码中设置的 1.7。

// TTF font needed for Unicode support in OCR texts
PDFont font = PDType0Font.load(document,
    PDDocument.class.getResourceAsStream("/org/apache/pdfbox/resources/ttf/LiberationSans-Regular.ttf"), true);

// Add metadata (needed by PDF/A)
XMPMetadata xmp = XMPMetadata.createXMPMetadata();
try {
    DublinCoreSchema dc = xmp.createAndAddDublinCoreSchema();
    dc.setTitle("THE DOCUMENT TITLE");
    dc.addCreator("THE AUTHOR");

    PDFAIdentificationSchema id = xmp.createAndAddPFAIdentificationSchema();
    id.setPart(2);
    id.setConformance("B");

    XmpSerializer serializer = new XmpSerializer();
    ByteArrayOutputStream baos = new ByteArrayOutputStream();
    serializer.serialize(xmp, baos, true);

    PDMetadata metadata = new PDMetadata(document);
    metadata.importXMPMetadata(baos.toByteArray());
    document.getDocumentCatalog().setMetadata(metadata);
} catch (BadFieldValueException e) {
    throw new IllegalArgumentException("", e);
}

// Set color profile (needed by PDF/A)
InputStream colorProfile = PDDocument.class.getResourceAsStream("/sRGB.icc");
PDOutputIntent intent = new PDOutputIntent(document, colorProfile);
intent.setInfo("sRGB IEC61966-2.1");
intent.setOutputCondition("sRGB IEC61966-2.1");
intent.setOutputConditionIdentifier("sRGB IEC61966-2.1");
intent.setRegistryName("http://www.color.org");
document.getDocumentCatalog().addOutputIntent(intent);

// Render all pages
for (IPage page : pages) {
    ((PdfboxPage)page).setFont(font);
    page.renderPage(this);
    document.addPage((PDPage) page.getPage());
}

document.setVersion(1.7f);
document.save(path);
document.close();

我做错了什么？

编辑1:

我可以看到PDF文件中有xpacket。它包括元数据。但看起来 PDFBox 没有以有效的方式写入这些数据(对于 veraPDF 和 pdfPilot)。

编辑2:

看起来 PDFBox 2.0.12 构建了无效的 PDF/A。我使用我们的商业 pdfPilot 程序转换了 PDF。 (PDF/A-1b)

PDFBox 将此写入 PDF 文件(-> 在 veraPDF 和 pdfPilot 中无效):

<?xpacket begin="
" id="W5M0MpCehiHzreSzNTczkc9d"?>
<x:xmpmeta xmlns:x="adobe:ns:meta/">
   <rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#">
      <rdf:Description xmlns:dc="http://purl.org/dc/elements/1.1/" rdf:about="">
         <dc:title>
            <rdf:Alt>
               <rdf:li lang="x-default">THE DOCUMENT TITLE</rdf:li>
            </rdf:Alt>
         </dc:title>
         <dc:creator>
            <rdf:Seq>
               <rdf:li>THE AUTHOR</rdf:li>
            </rdf:Seq>
         </dc:creator>
      </rdf:Description>
      <rdf:Description xmlns:pdfaid="http://www.aiim.org/pdfa/ns/id/" rdf:about="">
         <pdfaid:part>1</pdfaid:part>
         <pdfaid:conformance>B</pdfaid:conformance>
      </rdf:Description>
   </rdf:RDF>
</x:xmpmeta>
<?xpacket end="w"?>

pdfPilot 将此写入 PDF 文件(-> 在 veraPDF 和 pdfPilot 中有效):

<?xpacket begin="
" id="W5M0MpCehiHzreSzNTczkc9d"?>
<x:xmpmeta xmlns:x="adobe:ns:meta/" x:xmptk="Adobe XMP Core 5.6-c015 81.159809, 2016/11/11-01:42:16        ">
   <rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#">
      <rdf:Description rdf:about=""
            xmlns:dc="http://purl.org/dc/elements/1.1/"
            xmlns:xmp="http://ns.adobe.com/xap/1.0/"
            xmlns:xmpMM="http://ns.adobe.com/xap/1.0/mm/"
            xmlns:stEvt="http://ns.adobe.com/xap/1.0/sType/ResourceEvent#"
            xmlns:pdfaid="http://www.aiim.org/pdfa/ns/id/"
            xmlns:pdfaExtension="http://www.aiim.org/pdfa/ns/extension/"
            xmlns:pdfaSchema="http://www.aiim.org/pdfa/ns/schema#"
            xmlns:pdfaProperty="http://www.aiim.org/pdfa/ns/property#">
         <dc:format>application/pdf</dc:format>
         <dc:creator>
            <rdf:Seq>
               <rdf:li>AUTOR</rdf:li>
            </rdf:Seq>
         </dc:creator>
         <dc:title>
            <rdf:Alt>
               <rdf:li xml:lang="x-default">TITEL</rdf:li>
            </rdf:Alt>
         </dc:title>
         <xmp:ModifyDate>2019-01-11T11:42:22+01:00</xmp:ModifyDate>
         <xmp:CreateDate>2019-01-11T11:42:21+01:00</xmp:CreateDate>
         <xmp:MetadataDate>2019-01-11T11:42:22+01:00</xmp:MetadataDate>
         <xmpMM:DocumentID>uuid:b60f88c2-aa89-11b2-0a00-104bbf060000</xmpMM:DocumentID>
         <xmpMM:InstanceID>uuid:b61148b9-aa89-11b2-0a00-60d9faa0ff7f</xmpMM:InstanceID>
         <xmpMM:RenditionClass>default</xmpMM:RenditionClass>
         <xmpMM:VersionID>1</xmpMM:VersionID>
         <xmpMM:History>
            <rdf:Seq>
               <rdf:li rdf:parseType="Resource">
                  <stEvt:action>converted</stEvt:action>
                  <stEvt:instanceID>uuid:b60f88c3-aa89-11b2-0a00-902dfba0ff7f</stEvt:instanceID>
                  <stEvt:parameters>converted to PDF/A-1b</stEvt:parameters>
                  <stEvt:softwareAgent>pdfaPilot</stEvt:softwareAgent>
                  <stEvt:when>2019-01-11T11:42:22+01:00</stEvt:when>
               </rdf:li>
            </rdf:Seq>
         </xmpMM:History>
         <pdfaid:part>1</pdfaid:part>
         <pdfaid:conformance>B</pdfaid:conformance>
         <pdfaExtension:schemas>
            <rdf:Bag>
               <rdf:li rdf:parseType="Resource">
                  <pdfaSchema:namespaceURI>http://ns.adobe.com/xap/1.0/mm/</pdfaSchema:namespaceURI>
                  <pdfaSchema:prefix>xmpMM</pdfaSchema:prefix>
                  <pdfaSchema:schema>XMP Media Management Schema</pdfaSchema:schema>
                  <pdfaSchema:property>
                     <rdf:Seq>
                        <rdf:li rdf:parseType="Resource">
                           <pdfaProperty:category>internal</pdfaProperty:category>
                           <pdfaProperty:description>UUID based identifier for specific incarnation of a document</pdfaProperty:description>
                           <pdfaProperty:name>InstanceID</pdfaProperty:name>
                           <pdfaProperty:valueType>URI</pdfaProperty:valueType>
                        </rdf:li>
                        <rdf:li rdf:parseType="Resource">
                           <pdfaProperty:category>internal</pdfaProperty:category>
                           <pdfaProperty:description>The common identifier for all versions and renditions of a document.</pdfaProperty:description>
                           <pdfaProperty:name>OriginalDocumentID</pdfaProperty:name>
                           <pdfaProperty:valueType>URI</pdfaProperty:valueType>
                        </rdf:li>
                     </rdf:Seq>
                  </pdfaSchema:property>
               </rdf:li>
               <rdf:li rdf:parseType="Resource">
                  <pdfaSchema:namespaceURI>http://www.aiim.org/pdfa/ns/id/</pdfaSchema:namespaceURI>
                  <pdfaSchema:prefix>pdfaid</pdfaSchema:prefix>
                  <pdfaSchema:schema>PDF/A ID Schema</pdfaSchema:schema>
                  <pdfaSchema:property>
                     <rdf:Seq>
                        <rdf:li rdf:parseType="Resource">
                           <pdfaProperty:category>internal</pdfaProperty:category>
                           <pdfaProperty:description>Part of PDF/A standard</pdfaProperty:description>
                           <pdfaProperty:name>part</pdfaProperty:name>
                           <pdfaProperty:valueType>Integer</pdfaProperty:valueType>
                        </rdf:li>
                        <rdf:li rdf:parseType="Resource">
                           <pdfaProperty:category>internal</pdfaProperty:category>
                           <pdfaProperty:description>Amendment of PDF/A standard</pdfaProperty:description>
                           <pdfaProperty:name>amd</pdfaProperty:name>
                           <pdfaProperty:valueType>Text</pdfaProperty:valueType>
                        </rdf:li>
                        <rdf:li rdf:parseType="Resource">
                           <pdfaProperty:category>internal</pdfaProperty:category>
                           <pdfaProperty:description>Conformance level of PDF/A standard</pdfaProperty:description>
                           <pdfaProperty:name>conformance</pdfaProperty:name>
                           <pdfaProperty:valueType>Text</pdfaProperty:valueType>
                        </rdf:li>
                     </rdf:Seq>
                  </pdfaSchema:property>
               </rdf:li>
            </rdf:Bag>
         </pdfaExtension:schemas>
      </rdf:Description>
   </rdf:RDF>
</x:xmpmeta>
<?xpacket end="w"?>

如果我静态地将其写入 PDF 文件，它会生成一个有效的 PDF/A 文件:

String xmpData = "<?xpacket ......";
PDMetadata metadata = new PDMetadata(document);
metadata.importXMPMetadata(xmpData.getBytes());

编辑3:

添加此内容有效且简短:

<?xpacket begin="" id="W5M0MpCehiHzreSzNTczkc9d"?>
<x:xmpmeta xmlns:x="adobe:ns:meta/" >
    <rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#">
        <rdf:Description rdf:about=""
            xmlns:dc="http://purl.org/dc/elements/1.1/"
            xmlns:pdfaid="http://www.aiim.org/pdfa/ns/id/">
            <dc:format>application/pdf</dc:format>
            <dc:creator>
            <rdf:Seq>
                <rdf:li>AUTOR</rdf:li>
            </rdf:Seq>
            </dc:creator>
            <dc:title>
            <rdf:Alt>
                <rdf:li xml:lang="x-default">TITEL</rdf:li>
            </rdf:Alt>
            </dc:title>
            <pdfaid:part>1</pdfaid:part>
            <pdfaid:conformance>B</pdfaid:conformance>
        </rdf:Description>
    </rdf:RDF>
</x:xmpmeta>
<?xpacket end="w"?>

Answer 1

这是 CreatePDFA 示例生成的 XML 之间的区别

<rdf:li xml:lang="x-default">THE DOCUMENT TITLE</rdf:li> 

你得到的东西

<rdf:li lang="x-default">THE DOCUMENT TITLE</rdf:li>

这让我想起了 1 1/2 年前我们讨论过的一个问题 here .

引用我 2017 年的回答:这段代码

Transformer transformer = TransformerFactory.newInstance().newTransformer();

应返回 com.sun.org.apache.xalan.internal.xsltc.trax.TransformerImpl 类。如果没有，则调用

Transformer transformer =
    TransformerFactory.newInstance("com.sun.org.apache.xalan.internal.xsltc.trax.TransformerFactoryImpl", null).newTransformer(); 

或设置系统属性:

System.setProperty("javax.xml.transform.TransformerFactory", "com.sun.org.apache.xalan.internal.xsltc.trax.TransformerFactoryImpl");

我无法回答(因为你没有告诉)你是如何最终拥有这个变压器的，以及如果你改变它，你的应用程序的其余部分会发生什么。