如何使用OpenPDF添加段落和边框

Question

我正在使用OpenPDF生成带有添加到PDF的页眉和页脚图像的PDF文档。需要将一个段落添加到PDF的中心，其中一些文本内容根据输入请求是动态的，并且所有需求都被边框包围。我能够生成添加了页眉和页脚的PDf，但是在将段落添加到pdf和边框的中心时遇到问题。任何帮助表示赞赏。

我通过添加表格或使用画布尝试了不同的方法，但无法解决。

   public void generatePDF(String firstName, String lastName){
    try {
        Document doc = new Document();
        PdfWriter writer = PdfWriter.getInstance(doc, new FileOutputStream(DEST));
        //setting font family, color
        Font font = new Font(Font.HELVETICA, 16, Font.BOLDITALIC, Color.RED);
        doc.open();
        addHeaderImageToPDF(doc,writer);
        Paragraph para = new Paragraph("Hello! This PDF is created for "+firstName+" "+lastName, font);
        para.setAlignment(Element.ALIGN_MIDDLE);
        doc.add(para);
        addFooterImageToPDF(doc,writer);
        addBorderToPDF(doc);
        doc.close();
        writer.close();   
    } catch (Exception e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }   
}

private void addBorderToPDF(Document document){
    Rectangle rect= new Rectangle(531.5f,820,38.5f,0); // you can resize rectangle 
    rect.enableBorderSide(1);
    rect.enableBorderSide(2);
    rect.enableBorderSide(4);
    rect.enableBorderSide(8);
    rect.setBorderColor(Color.BLACK);
    rect.setBorderWidth(2);
    document.add(rect);
}

private void addHeaderImageToPDF(Document document, PdfWriter writer){
    try {
        Image image = Image.getInstance(HEADER_IMAGE_PATH);
        //image = Image.getInstance(IMAGE_PATH);
        image.scalePercent(50f);
        //image.setAbsolutePosition(0, (float) (PageSize.A4.getHeight() - 20.0));
        image.setAbsolutePosition(40, 675);
        System.out.println(image.getScaledHeight());
        document.add(image);
        image.scaleToFit(100f, 100f);
        //document.add(image);
    } catch (Exception e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }
}

private void addFooterImageToPDF(Document document, PdfWriter writer){
    try {
        Image image = Image.getInstance(FOOTER_IMAGE_PATH);
        //image = Image.getInstance(IMAGE_PATH);
        image.scalePercent(50f);
        //image.setAbsolutePosition(0, (float) (PageSize.A4.getHeight() - 20.0));
        image.setAbsolutePosition(40, 450);
        System.out.println(image.getScaledHeight());
        document.add(image);
        image.scaleToFit(100f, 100f);
        //document.add(image);
    } catch (Exception e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }
}

想要在段落的中间添加段落，并且PDF的整个内容都应该用深蓝色边框包围。任何帮助表示赞赏。

Answer 1

由于给定的标签itext，pdfbox和openpdf隐含了PDF库选择的自由度，此处示例使用iText 7创建带有深蓝色边框的居中段落（v7.1.7）：

带有边框的居中段落

String firstName = "Mister";
String lastName = "Nine";
try (   PdfWriter pdfWriter = new PdfWriter(new File("CenterParagraph.pdf"));
        PdfDocument pdfDocument = new PdfDocument(pdfWriter);
        Document document = new Document(pdfDocument)   ) {
    Paragraph paragraph = new Paragraph("Hello! This PDF is created for "+firstName+" "+lastName);
    paragraph.setWidth(100).setBorder(new SolidBorder(new DeviceRgb(0f, 0f, 0.6f), 3));
    PageSize box = pdfDocument.getDefaultPageSize();
    document.showTextAligned(paragraph, (box.getLeft() + box.getRight()) / 2, (box.getTop() + box.getBottom()) / 2,
            TextAlignment.CENTER, VerticalAlignment.MIDDLE);
}

（ShowTextAtPosition测试testShowCenteredBorderedParagraph）

导致

在页面中间。

带有页眉和页脚图像以及页面边框的居中段落

String firstName = "Mister";
String lastName = "Nine";

Image img = null;
try (   InputStream imageResource = IMAGE_INPUT_STREAM ) {
    ImageData data = ImageDataFactory.create(StreamUtil.inputStreamToArray(imageResource));
    img = new Image(data);
    img.scaleToFit(100f, 100f);
}

try (   PdfWriter pdfWriter = new PdfWriter(new File("CenterParagraphWithExtras.pdf"));
        PdfDocument pdfDocument = new PdfDocument(pdfWriter);
        Document document = new Document(pdfDocument)   ) {
    PageSize box = pdfDocument.getDefaultPageSize();

    Paragraph paragraph = new Paragraph("Hello! This PDF is created for "+firstName+" "+lastName);
    paragraph.setWidth(100);
    document.showTextAligned(paragraph, (box.getLeft() + box.getRight()) / 2, (box.getTop() + box.getBottom()) / 2,
            TextAlignment.CENTER, VerticalAlignment.MIDDLE);

    PdfCanvas pdfCanvas = new PdfCanvas(pdfDocument.getLastPage());
    Rectangle borderRectangle = new Rectangle(box.getLeft() + 5, box.getBottom() + 5, box.getWidth() - 10, box.getHeight() - 10);
    pdfCanvas.setColor(new DeviceRgb(0f, 0f, 0.6f), false);
    pdfCanvas.setLineWidth(3);
    pdfCanvas.rectangle(borderRectangle);
    pdfCanvas.stroke();

    img.setFixedPosition(box.getLeft() + 40, box.getTop() - 150);
    document.add(img);
    img.setFixedPosition(box.getLeft() + 40, box.getBottom() + 50);
    document.add(img);
}

导致