如何使用 IText 获取可移植合集 PDF 的页数或使用 Java 获取任何函数

Question

PdfReader reader = new PdfReader(pdfFile, new byte[0]);
pages = reader.getNumberOfPages();

假设便携式集合中有两个pdf（每个PDF包含2页）。当我尝试获取页面数时，它只返回1。我认为它正在考虑便携式收藏文件的封面。有没有办法获得便携式整理的页数？我使用的是 Java 11 和 IText 5.5 版本。

Answer 1

我找到了解决方案，但我认为没有必要检查以下内容，解决方案不是获取总pdf页码的有效方法。private int getNumberOfPages(PdfReader reader) {&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; int pages = 0;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; PdfObject obj;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; for (int i = 1; i <= reader.getXrefSize(); i++) {&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; obj = reader.getPdfObject(i);&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; if (obj != null && obj.isStream()) {&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; PRStream stream = (PRStream)obj;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; byte[] b;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; try {&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; b = PdfReader.getStreamBytes(stream);&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; PdfReader pdfReader = new PdfReader(b);&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; pages += pdfReader.getNumberOfPages();&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; } catch(InvalidPdfException e) {&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; } catch (IOException e) {&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; }&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; }&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; }&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; if (pages == 0) {&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; pages = reader.getNumberOfPages();&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; }&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; return pages;&nbsp; &nbsp; &nbsp; &nbsp; }