以编程方式合并加密的pdf文件异常

Question

我一直在使用以下代码以编程方式合并加密的 pdf 文件。

public void mergeMyFiles(String filesToBeMerged[], String mergedFileLocation, String password) {
    try {
        int pageOffset = 0;
        ArrayList masterBookMarkList = new ArrayList();

        int fileIndex = 0;
        String outFile = mergedFileLocation;
        Document document = null;
        PdfCopy writer = null;
        PdfReader reader = null;
        PdfReader.unethicalreading = true;
        for (fileIndex = 0; fileIndex < filesToBeMerged.length; fileIndex++) {
            /**
             * Create a reader for the file that we are reading
             */
            reader = new PdfReader(filesToBeMerged[fileIndex], password.getBytes());
            /**
             * Replace all the local named links with the actual destinations.
             */
            reader.consolidateNamedDestinations();

            /**
             * Retrieve the total number of pages for this document
             */
            int totalPages = reader.getNumberOfPages();

            /**
             * Get the list of bookmarks for the current document
             * If the bookmarks are not empty, store the bookmarks
             * into a master list
             */
            List bookmarks = SimpleBookmark.getBookmark(reader);
            if (bookmarks != null) {
                if (pageOffset != 0)
                    SimpleBookmark.shiftPageNumbers(bookmarks, pageOffset,
                        null);
                masterBookMarkList.addAll(bookmarks);
                System.out.println("Bookmarks found and storing...");
            } else {
                System.out.println("No bookmarks in this file...");
            }
            pageOffset += totalPages;

            /**
             * Merging the files to the first file.
             * If we are passing file1, file2 and file3,
             * we will merge file2 and file3 to file1.
             */
            if (fileIndex == 0) {
                /**
                 * Create the document object from the reader
                 */
                document = new Document(reader.getPageSizeWithRotation(1));

                /**
                 * Create a pdf write that listens to this document.
                 * Any changes to this document will be written the file
                 *
                 * outFile is a location where the final merged document
                 * will be written to.
                 */

                System.out.println("Creating an empty PDF...");
                writer = new PdfCopy(document, new FileOutputStream(outFile));
                /**
                 * Open this document
                 */
                document.open();
            }
            /**
             * Add the conent of the file into this document (writer).
             * Loop through multiple Pages
             */
            System.out.println("Merging File: " + filesToBeMerged[fileIndex]);
            PdfImportedPage page;
            for (int currentPage = 1; currentPage <= totalPages; currentPage++) {
                page = writer.getImportedPage(reader, currentPage);
                writer.addPage(page);
            }

            /**
             * This will get the documents acroform.
             * This will return null if no acroform is part of the document.
             *
             * Acroforms are PDFs that have been turned into fillable forms.
             */
            System.out.println("Checking for Acroforms");
            PRAcroForm form = reader.getAcroForm();
            if (form != null) {
                //writer.copyAcroForm(reader);
                writer.addDocument(reader);
                System.out.println("Acroforms found and copied");
            } else
                System.out.println("Acroforms not found for this file");

            System.out.println();
        }
        /**
         * After looping through all the files, add the master bookmarklist.
         * If individual PDF documents had separate bookmarks, master bookmark
         * list will contain a combination of all those bookmarks in the
         * merged document.
         */
        if (!masterBookMarkList.isEmpty()) {
            writer.setOutlines(masterBookMarkList);
            System.out.println("All bookmarks combined and added");

        } else {
            System.out.println("No bookmarks to add in the new file");

        }

        /**
         * Finally Close the main document, which will trigger the pdfcopy
         * to write back to the filesystem.
         */
        document.close();
    } catch (Exception e) {
        e.printStackTrace();
    }
}

我最近在尝试在这行代码中创建 pdfReader 时开始收到此错误：

reader = new PdfReader(filesToBeMerged[fileIndex], password.getBytes());

com.itextpdf.text.exceptions.InvalidPdfException: Unknown encryption type R = 6 at com.itextpdf.text.pdf.PdfReader.readPdf(PdfReader.java:738) at com.itextpdf.text.pdf.PdfReader.(PdfReader.java:181) at com.itextpdf.text.pdf.PdfReader.(PdfReader.java:219) at com.itextpdf.text.pdf.PdfReader.(PdfReader.java:207) at com.project.mainPageShop.mergeMyFiles(mainPageShop.java:4368) at com.project.mainPageShop$DownloadFileAsync.onPostExecute(mainPageShop.java:11757) at com.project.mainPageShop$DownloadFileAsync.onPostExecute(mainPageShop.java:11628) at android.os.AsyncTask.finish(AsyncTask.java:755) at android.os.AsyncTask.access0(AsyncTask.java:192) at android.os.AsyncTask$InternalHandler.handleMessage(AsyncTask.java:772) at android.os.Handler.dispatchMessage(Handler.java:107) at android.os.Looper.loop(Looper.java:237) at android.app.ActivityThread.main(ActivityThread.java:7814) at java.lang.reflect.Method.invoke(Native Method) at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:493) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1068)

请注意密码是正确的，以前使用此代码工作的同一个文件现在引发此异常。

更新：

我使用以下代码使用 com.itextpdf:itext7-core:7.0.2

public void mergePDFFiles(String FILE1, String FILE2, String mergedFileLocation, String password) {
    try {
        PdfReader pdf1 = new PdfReader(FILE1);
        pdf1.setUnethicalReading(true);
        PdfReader pdf2 = new PdfReader(FILE2);
        pdf2.setUnethicalReading(true);
        PdfDocument pdfDocument = new PdfDocument(pdf1, new PdfWriter(mergedFileLocation));
        PdfDocument pdfDocument2 = new PdfDocument(pdf2);

        PdfMerger merger = new PdfMerger(pdfDocument);
        merger.merge(pdfDocument2, 1, pdfDocument2.getNumberOfPages());

        pdfDocument2.close();
        pdfDocument.close();
    } catch (IOException e) {
        e.printStackTrace();
    }
}

这是 logcat 结果：

FATAL EXCEPTION: main Process: com.project, PID: 7665 com.itextpdf.kernel.PdfException: Unknown encryption type R == 6. at com.itextpdf.kernel.pdf.PdfEncryption.readAndSetCryptoModeForStdHandler(PdfEncryption.java:508) at com.itextpdf.kernel.pdf.PdfEncryption.(PdfEncryption.java:181) at com.itextpdf.kernel.pdf.PdfReader.readDecryptObj(PdfReader.java:1061) at com.itextpdf.kernel.pdf.PdfReader.readPdf(PdfReader.java:531) at com.itextpdf.kernel.pdf.PdfDocument.open(PdfDocument.java:1585) at com.itextpdf.kernel.pdf.PdfDocument.(PdfDocument.java:281) at com.itextpdf.kernel.pdf.PdfDocument.(PdfDocument.java:249) at com.project.mainPageShop.mergePDFFiles(mainPageShop.java:4353) at com.neelwafurat.iKitabForAndroid.mainPageShop$DownloadFileAsync.onPostExecute(mainPageShop.java:11788) at com.project.mainPageShop$DownloadFileAsync.onPostExecute(mainPageShop.java:11659) at android.os.AsyncTask.finish(AsyncTask.java:755) at android.os.AsyncTask.access0(AsyncTask.java:192) at android.os.AsyncTask$InternalHandler.handleMessage(AsyncTask.java:772) at android.os.Handler.dispatchMessage(Handler.java:107) at android.os.Looper.loop(Looper.java:237) at android.app.ActivityThread.main(ActivityThread.java:7814) at java.lang.reflect.Method.invoke(Native Method) at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:493) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1068)

错误发生在以下行：

PdfDocument pdfDocument = new PdfDocument(pdf1, new PdfWriter(mergedFileLocation));

在下面的链接中找到使用密码的示例加密 pdf 文件：123456

https://smallpdf.com/shared#st=8921059d-6615-4264-a3f6-c76d476dc168&fn=test+1.pdf&ct=1602755420749&tl=share-document&rf=link

https://smallpdf.com/shared#st=7d3c11c7-b34d-4399-bc03-c66b7be788d0&fn=test+2.pdf&ct=1602755505331&tl=share-document&rf=link

Answer 1

iText 5 或 iText 7.0.2 不支持标准安全处理程序的修订版 6。它是在支持 PDF 2.0 的情况下在 iText 7.1.0 中引入的。

我稍微调整了您的代码示例以进行测试。请注意，您没有将密码传递给 PdfReader 实例。

另请注意，您为示例 PDF (123456) 共享的密码是用户密码，而不是所有者密码。

一个用户密码，也叫打开密码，用于打开一个PDF文档，即允许访问内容。所有其他限制均由 所有者密码 处理，也称为 权限密码，例如allowing/preventing 正在打印文档。

对于您的示例文档，设置了打开密码和权限密码：

如果您有可用的所有者密码，您应该在处理 PDF 时使用它，即将它传递给 PdfReader 实例。这使您可以避免 unethicalreading 设置。

测试代码：

public void mergePDFFiles(String FILE1, String FILE2, String mergedFileLocation, String password)
{
    try {
        PdfReader pdf1 = new PdfReader(FILE1,
            new ReaderProperties().setPassword(password.getBytes()));
        pdf1.setUnethicalReading(true);
        PdfReader pdf2 = new PdfReader(FILE2,
            new ReaderProperties().setPassword(password.getBytes()));
        pdf2.setUnethicalReading(true);
        PdfDocument pdfDocument = new PdfDocument(pdf1, new PdfWriter(mergedFileLocation));
        PdfDocument pdfDocument2 = new PdfDocument(pdf2);

        PdfMerger merger = new PdfMerger(pdfDocument);
        merger.merge(pdfDocument2, 1, pdfDocument2.getNumberOfPages());

        pdfDocument2.close();
        pdfDocument.close();
    } catch (IOException e) {
        e.printStackTrace();
    }
}

iText 7.0.2 不支持修订版 6，如您所见：

Exception in thread "main" com.itextpdf.kernel.PdfException: Unknown encryption type R == 6.
    at com.itextpdf.kernel.pdf.PdfEncryption.readAndSetCryptoModeForStdHandler(PdfEncryption.java:508)
    at com.itextpdf.kernel.pdf.PdfEncryption.<init>(PdfEncryption.java:181)
    at com.itextpdf.kernel.pdf.PdfReader.readDecryptObj(PdfReader.java:1061)
    at com.itextpdf.kernel.pdf.PdfReader.readPdf(PdfReader.java:531)
    at com.itextpdf.kernel.pdf.PdfDocument.open(PdfDocument.java:1585)
    at com.itextpdf.kernel.pdf.PdfDocument.<init>(PdfDocument.java:281)
    at com.itextpdf.kernel.pdf.PdfDocument.<init>(PdfDocument.java:249)

从 iText 7.1.0 到当前版本 (7.1.13)，您的 2 个示例文件将正确合并，生成一个 4 页的输出文件。

以编程方式合并加密的pdf文件异常

Merge encrypted pdf file programmatically exception

java

pdf

android

itext

itext7