java - 我有一张印章，上面有复选标记和当前日期。我需要使用itext和java将此图章添加到pdf中的所有页面

Question

我有一张印章，上面有复选标记和当前日期。
我需要使用 itext 和 java 单击按钮将此图章添加到 pdf 中的所有页面。
印章是一种具有文本字段的表单，其中使用 JavaScript 自动输入日期。

PdfReader reader = new PdfReader(src);
PdfReader s_reader = new PdfReader(stationery);
// Create the stamper
PdfStamper stamper = new PdfStamper(reader, new FileOutputStream(dest));
// Add the stationery to each page
PdfImportedPage page = stamper.getImportedPage(s_reader, 1);
int n = reader.getNumberOfPages();
PdfContentByte background;
for (int i = 1; i <= n; i++) {
    background = stamper.getUnderContent(i);
    background.addTemplate(page, 0, 0);
}
// Close the stamper
stamper.close();
reader.close();
s_reader.close();

现在，如何从 pdf 中获取保存的图章(表单)，向其添加当前日期以及如何将此图章添加到 Pdf 文档的所有页面？
需要 JavaScript 吗？

Answer 1

创建 pdf

private static final Font headerFont = new Font(Font.FontFamily.TIMES_ROMAN, 9,
            Font.BOLD, BaseColor.BLACK);
Document document = new Document(PageSize.A4, 20, 20, 120, 50);
PdfWriter writer = PdfWriter.getInstance(document, new FileOutputStream(realPath + "/PdfTable.pdf"));
        writer.setBoxSize("art", new Rectangle(36, 54, 559, 788));
        HeaderFooterOfPdf event = new HeaderFooterOfPdf(batchDate);
        writer.setPageEvent(event);
        document.open();
//to create table
PdfPTable vppTable = new PdfPTable(new float[]{3, 7, 9, 3, 5, 3, 3, 3, 4});
        vppTable.setWidthPercentage(100f);
//pdf table header
        vppTable.addCell(new PdfPCell(new Phrase("Your column name", headerFont)));
        vppTable.addCell(new PdfPCell(new Phrase("Your column name", headerFont)));
        vppTable.setHeaderRows(1);

//to add cell data
PdfPCell slNoCell = new PdfPCell(new Phrase("your data", contentFont));
            slNoCell.setVerticalAlignment(Element.ALIGN_MIDDLE);
            slNoCell.setPaddingLeft(15f);
            vppTable.addCell(slNoCell);

document.add(vppTable);
document.close();

HeaderFooterOfPdf 类

public class HeaderFooterOfPdf extends PdfPageEventHelper{

public HeaderFooterOfPdf(String batchDate){
        this.batchDate = batchDate;
    }

@Override
    public void onOpenDocument(PdfWriter writer, Document document) {
    }

@Override
    public void onStartPage(PdfWriter writer, Document document) {
//do what you want to enter on header
}

@Override
    public void onEndPage(PdfWriter writer, Document document) {
//do what you want to enter on footer
}
}