如何使用itextpdf-5.4.4.jar添加多个回复注释

Question

在sandbox.annotations.AddInReplyTo中，有一个示例只创建一个回复注释，我想添加两个以上的回复注释，参考示例，我想使用以下代码来停止两个回复注释。但是，创建的pdf可以在adobe acrobat pro或adobe reader中打开，但是回复注释的内容都是“Hello PDF 01”，replySticky2的“Hello PDF 02”无法显示，我的代码有问题吗？谢谢你的帮助!!!

    public void manipulatePdf(String src, String dest) throws IOException, DocumentException {
    PdfReader reader = new PdfReader(src);
    PdfDictionary page = reader.getPageN(1);
    PdfArray annots = page.getAsArray(PdfName.ANNOTS);
    PdfDictionary sticky = annots.getAsDict(0);
    PdfArray stickyRect = sticky.getAsArray(PdfName.RECT);
    PdfDictionary popup = annots.getAsDict(1);
    PdfStamper stamper = new PdfStamper(reader, new FileOutputStream(dest));
    PdfWriter writer = stamper.getWriter();
    Rectangle stickyRectangle = new Rectangle(
        stickyRect.getAsNumber(0).floatValue(), stickyRect.getAsNumber(1).floatValue(),
        stickyRect.getAsNumber(2).floatValue(), stickyRect.getAsNumber(3).floatValue()
    );
    PdfAnnotation replySticky = PdfAnnotation.createText(
            writer, stickyRectangle, "Reply-01", "Hello PDF 01", true, "Comment");
    replySticky.put(PdfName.IRT, annots.getAsIndirectObject(0));
    stamper.addAnnotation(replySticky, 1);        

    PdfAnnotation replySticky2 = PdfAnnotation.createText(
            writer, stickyRectangle, "Reply-02", "Hello PDF 02", true, "Comment");
    replySticky2.put(PdfName.IRT, annots.getAsIndirectObject(0));
    stamper.addAnnotation(replySticky2, 1);

    stamper.close();
}