OpenPDF的学习文档（第八章·拆分合并PDF）

合并PDF

/**
 * 合并PDF
 * @param list 输入流 列表
 * @return 输出流
 */
public static ByteArrayOutputStream mergerPDF(List<InputStream> list) throws IOException {
    ByteArrayOutputStream stream = new ByteArrayOutputStream();
    Document document = new Document();
    PdfCopy copy = new PdfSmartCopy(document, stream);
    document.open();
    for (InputStream is : list) {
        PdfReader reader = new PdfReader(is);
        for (int i = 1; i <= reader.getNumberOfPages(); i++) {
            copy.addPage(copy.getImportedPage(reader, i));
        }
        reader.close();
    }
    copy.close();
    document.close();
    return stream;
}

拆分PDF

/**
 * 拆分PDF
 * @param is 输入流
 * @return 输出流 列表
 */
public static List<ByteArrayOutputStream> splitPDF(InputStream is) throws IOException {
    PdfReader reader = new PdfReader(is);
    List<ByteArrayOutputStream> result = new ArrayList<>();
    for (int i = 1; i <= reader.getNumberOfPages(); i++) {
        ByteArrayOutputStream stream = new ByteArrayOutputStream();
        Document document = new Document();
        PdfSmartCopy copy = new PdfSmartCopy(document, stream);
        document.open();
        copy.addPage(copy.getImportedPage(reader, i));
        copy.close();
        document.close();
        result.add(stream);
    }
    reader.close();
    return result;
}