PdfCopy和PdfACopy之间的差异

Question

我编写了一个函数，使用iText 5.5.13（使用iText教程中的说明）将文件作为附件嵌入到PDF/A-3A文档中。

如果我使用类PdfCopy附加文件，结果是一个正确的PDF文件，但它并不声称是PDF/a（也许它匹配了所有的要求，但它没有说）。

public static File embedFile(File inputPdf) {

    File outputPdf = new File("./test.pdf");

    PdfReader reader = new PdfReader(inputPdf.getAbsolutePath());
    Document document = new com.itextpdf.text.Document();
    OutputStream os = new FileOutputStream(outputPdf.getAbsolutePath());
    PdfACopy copy = new PdfACopy(document, os, PdfAConformanceLevel.PDF_A_3A); // Output doc doesn't work
    // PdfCopy copy = new PdfCopy(document, os); // Output doc works but doesn't claim to be PDF/A

    document.open();
    copy.addDocument(reader);

    // Include attachment (extactly as in the sample tutorial)
    PdfDictionary parameters = new PdfDictionary();
    parameters.put(PdfName.MODDATE, new PdfDate());
    PdfFileSpecification fileSpec = PdfFileSpecification.fileEmbedded(
        writer, "./src/main/resources/com/itextpdf/invoice.xml",
        "invoice.xml", null, "application/xml", parameters, 0);
    fileSpec.put(new PdfName("AFRelationship"), new PdfName("Data"));
    writer.addFileAttachment("invoice.xml", fileSpec);
    PdfArray array = new PdfArray();
    array.add(fileSpec.getReference());
    writer.getExtraCatalog().put(new PdfName("AF"), array);

    os.flush();
    reader.close();
    document.close();
    os.close();
    copy.close();

    return outputPdf;
}

Answer 1

正如Bruno Lowagie在评论中指出的，这在iText 7中是可能的。这里的函数可以帮助某人：

public static File embedFile(File inputPdf, File embeddedFile, String embeddedFileName, String embeddedFileMimeType)
        throws IOException {

    File outputPdf = new File("./test.pdf");

    PdfReader reader = new PdfReader(inputPdf.getAbsolutePath());
    PdfWriter writer = new PdfWriter(outputPdf.getAbsolutePath());
    PdfADocument pdfDoc = new PdfADocument(reader, writer);

    // Add attachment
    PdfDictionary parameters = new PdfDictionary();
    parameters.put(PdfName.ModDate, new PdfDate().getPdfObject());
    PdfFileSpec fileSpec = PdfFileSpec.createEmbeddedFileSpec(pdfDoc, embeddedFile.getAbsolutePath(), embeddedFileName,
            embeddedFileName, new PdfName(embeddedFileMimeType), parameters, PdfName.Data);
    fileSpec.put(new PdfName("AFRelationship"), new PdfName("Data"));
    pdfDoc.addFileAttachment(embeddedFileName, fileSpec);
    PdfArray array = new PdfArray();
    array.add(fileSpec.getPdfObject().getIndirectReference());
    pdfDoc.getCatalog().put(new PdfName("AF"), array);

    pdfDoc.close();
    reader.close();
    writer.close();

    return outputPdf;

}