How to Generate PDFs with iText in Spring Boot – A Step‑by‑Step Guide

Environment: Spring Boot 2.3.10.RELEASE with iTextPDF 5.5.13.2

Dependencies

<dependency>
  <groupId>com.itextpdf</groupId>
  <artifactId>itextpdf</artifactId>
  <version>5.5.13.2</version>
</dependency>
<dependency>
  <groupId>com.itextpdf</groupId>
  <artifactId>itext-asian</artifactId>
  <version>5.2.0</version>
</dependency>

Note: The itext-asian dependency is optional for compilation but required to display Asian characters correctly.

Creating the Template

First create a template using Microsoft Word.

Save the Word document as a PDF file.

Open the saved PDF with Adobe Acrobat 9 Pro.

1. Open Adobe Acrobat 9 Pro

Click the Form Wizard in the Forms menu.

Note: The arrow points to a text field that must be added to capture the position for inserting an image.

PDF Generation Utility Class

public static void genPdf(Student student, HttpServletResponse response) {
    try {
        ClassPathResource resource = new ClassPathResource("tml/pdf/student.pdf");
        PdfReader pdfReader = new PdfReader(resource.getInputStream());
        ByteArrayOutputStream baos = new ByteArrayOutputStream();
        PdfStamper stamper = new PdfStamper(pdfReader, baos);
        AcroFields af = stamper.getAcroFields();
        af.setField("name", student.getName());
        af.setField("major", student.getMajor());
        af.setField("sno", student.getSno());
        af.setField("place", student.getPlace());
        // Insert image
        String imgUrl = new ClassPathResource("static/1.png").getURL().getPath();
        FieldPosition position = af.getFieldPositions("header").get(0);
        int pageNo = position.page;
        Rectangle signRect = position.position;
        float x = signRect.getLeft();
        float y = signRect.getBottom();
        Image image = Image.getInstance(imgUrl);
        PdfContentByte under = stamper.getOverContent(pageNo);
        image.scaleToFit(signRect.getWidth(), signRect.getHeight());
        image.setAbsolutePosition(x, y);
        under.addImage(image);
        // Flatten the form so the PDF cannot be edited
        stamper.setFormFlattening(true);
        stamper.close();
        // Respond to client
        String downloadFileName = new String((student.getName() + "个人信息.pdf").getBytes("utf-8"), "iso8859-1");
        response.addHeader("Content-Disposition", "attachment;filename=" + downloadFileName);
        OutputStream os = new BufferedOutputStream(response.getOutputStream());
        Document doc = new Document();
        PdfCopy copy = new PdfCopy(doc, os);
        doc.open();
        PdfImportedPage importPage = copy.getImportedPage(new PdfReader(baos.toByteArray()), 1);
        copy.addPage(importPage);
        doc.close();
        response.setContentType("application/pdf");
        os.flush();
        os.close();
    } catch (Exception e) {
        logger.error("生成PDF错误：{}", e);
    }
}

API Endpoint

@GetMapping("/download")
public void download() {
    Student student = new Student();
    student.setMajor("计算机生命与科学");
    student.setName("李逵");
    student.setPlace("北京");
    student.setSno("S001");
    PdfUtil.genPdf(student, response);
}

Generated Document

Done!!!