SpringBoot uses iText7 to convert HTML to PDF and add header footer watermark

        <!-- itext7 -->
        <dependency>
            <groupId></groupId>
            <artifactId>kernel</artifactId>
            <version>7.2.4</version>
        </dependency>
 
        <dependency>
            <groupId></groupId>
            <artifactId>io</artifactId>
            <version>7.2.4</version>
        </dependency>
 
        <dependency>
            <groupId></groupId>
            <artifactId>forms</artifactId>
            <version>7.2.4</version>
        </dependency>
 
        <dependency>
            <groupId></groupId>
            <artifactId>layout</artifactId>
            <version>7.2.4</version>
        </dependency>
 
        <dependency>
            <groupId></groupId>
            <artifactId>svg</artifactId>
            <version>7.2.4</version>
        </dependency>
 
        <!-- font-asian ForitextUsing East Asian Fonts -->
        <dependency>
            <groupId></groupId>
            <artifactId>font-asian</artifactId>
            <version>7.2.4</version>
        </dependency>
 
        <!-- html2pdf For转换htmlforpdf -->
        <dependency>
            <groupId></groupId>
            <artifactId>html2pdf</artifactId>
            <version>4.0.1</version>
        </dependency>

/**
      *
      * @param pdf_path PDF file save path
      * @param pdf_name PDF file name
      * @param cookie User information
      * @param waterContent Watermark content
      * @return
      * @throws AppException
      */
    public PmsLXPDF createHtmlToPDF(String pdf_path, String pdf_name, String cookie, String waterContent) throws AppException {
        ("Start createPDF");
        PmsLXPDF pdf = new PmsLXPDF();
        String pdfViewUrl = "This is the interface path, generate jsp template";
 
        String url = ();
        ("createPDFMethod Gettingmeurl[{}]",url);
 
        (url + pdfViewUrl, pdf_path, cookie, waterContent);
 
        File file = new File(pdf_path);
        if (file == null || !()) {
            throw new AppException("The project report failed to generate pdf!");
        }
        try {
            //You can do some saving operations        } catch (Exception e) {
            ("Exception happened", e);
        }
        //((id));
        ("createPDF ends");
 
        return pdf;
    }
 
 
 
 
/**
      * html to pdf
      *
      * @param srcPath html path, can be a path on the hard disk or a network path
      * @param destPath pdf save path
      * @return Return true if the conversion is successful
      */
    public static boolean convert(String srcPath, String destPath, String cookie, String waterContent) {
        if (!(destPath)) {
            ("The target path PDF file already exists, and the PDF generation failed:" + destPath);
            return false;
        }
        ("convertMethod passed insrcPath[{}],cookie[{}]",srcPath,cookie);
        InputStream in = null;
        OutputStream out = null;
        HttpURLConnection connection = null;
        try {
            if (("http")) {
                ("convertMethod passed insrcPath[{}],Need to entercookiebranch of",srcPath);
                URL url = new URL(srcPath);
                int connectTimeout = (("xxx", "30000"));
                int readTimeout = (("xxx", "30000"));
                connection = (HttpURLConnection) ();
                // Set the timeout time to connect to the host server                (connectTimeout);
                // Set the time to read the data returned remotely                (readTimeout);
                if ((cookie)) {
                    // Set cookies                    String cookies = "SESSION=".concat(cookie);
                    ("Cookie", cookies);
                }
                // Connect and get response                ();
                in = ();
            } else {
                ("convertMethod passed insrcPath[{}],进入了不需要登录branch of",srcPath);
                in = new FileInputStream(srcPath);
            }
            out = new ByteArrayOutputStream();
            (in, out);
        } catch (Throwable t) {
            ("Reading this file failed:" + srcPath, t);
            return false;
        } finally {
            (in);
            (out);
            if (connection != null) {
                ();// Close the remote connection            }
        }
        
        String html = ();
 
        converCreatPdf(destPath, cookie, html, waterContent);
        
        return true;
    }
 
 
 
private static boolean converCreatPdf(String destPath, String cookie, String html, String waterContent) {
        try (OutputStream fos = new FileOutputStream(destPath)) {
            //Convert html to pdf            PdfWriter pdfWriter = new PdfWriter(fos);
            PdfDocument pdfDoc = new PdfDocument(pdfWriter);
 
            // Unified page header settings            String header = "I'm a header";
            Header headerHandler = new Header(header);
            (PdfDocumentEvent.START_PAGE, headerHandler);
 
            // Unified footer settings            Footer footerHandler = new Footer();
            (PdfDocumentEvent.END_PAGE, footerHandler);
 
            if ((waterContent)) {
                // Add watermark                PdfWaterMarker pdfWaterMarker = new PdfWaterMarker(waterContent);
                (PdfDocumentEvent.END_PAGE, pdfWaterMarker);
            }
 
            // You need to create a document instead of directly generating a pdf file (because directly generating a pdf file will close the stream)            ConverterProperties converterProperties = getConverterProperties(cookie);
            Document document = (html, pdfDoc, converterProperties);
 
            // flush triggers the write operation, and the registered event handler will be triggered at this time            ();
 
            // Only after the document object is finished writing can you start writing the total page number            ("Total number of PDF pages:" + ().getNumberOfPages());
            (pdfDoc);
            ();
        } catch (Throwable t) {
            ("Creating PDF failed:" + destPath, t);
            return false;
        }
        return true;
    }
 
 
public static ConverterProperties getConverterProperties(String cookie) {
        ConverterProperties converterProperties = new ConverterProperties();
        FontProvider fontProvider = getFontProvider();
        (fontProvider);
        CookieResourceRetriever myResourceRetriever = new CookieResourceRetriever(cookie);
        (myResourceRetriever);
        return converterProperties;
    }
 
 
public void writeTotal(PdfDocument pdf) {
            Canvas canvas = new Canvas(placeholder, pdf);
            (8);
            if (font != null) {
                // Settings support Chinese                ();
                // Total number of pages written in placeholders                (("/Total [%d] pages", ()), 0, descent,
                    );
            }
            ();
        }

public class HtmlPrittifier {
 
    /**
      * Standardize HTML to complete missing closed tags
      *
      * @param in
      * @param out
      */
    public static void fixHtml(InputStream in, OutputStream out) {
        // obtain a new Tidy instance
        Tidy tidy = new Tidy();
 
        // set desired config options using tidy setters
        (true);
 
        ("utf8");
 
        (true);
 
        (1024);
 
        (true);
 
        (true);
 
        (false);
 
        ("utf8");
 
        (false);
 
        // output document even if errors were found. Prevent some custom tags from matching and causing pdf not to output        (true);
 
        // Do not convert uri to prevent Chinese in uri from being included, and will convert non-ascii codes to hexadecimal, resulting in the Chinese picture link not being found.        (false);
 
        (in, out);
    }
 
    /**
      * Standardize HTML to complete missing closed tags
      *
      * @param htmlString
      */
    @SneakyThrows
    public static String fixHtml(String htmlString) {
        ByteArrayInputStream in = new ByteArrayInputStream(("UTF-8"));
        ByteArrayOutputStream out = new ByteArrayOutputStream();
        fixHtml(in, out);
        return ();
    }
 
}

private static PdfFont createDefaultFont() throws IOException {
        return ("STSong-Light", "UniGB-UCS2-H");
}
 
protected static class PdfWaterMarker implements IEventHandler {
 
        private PdfFont font;
        private String waterContent;
 
        public PdfWaterMarker(String waterContent) {
             = waterContent;
            try {
                 = createDefaultFont();
            } catch (IOException e) {
                ("PDF Header failed to set Chinese fonts", e);
            }
        }
 
        @Override
        public void handleEvent(Event event) {
            PdfDocumentEvent docEvent = (PdfDocumentEvent) event;
            PdfDocument pdfDoc = ();
            PdfPage page = ();
            Rectangle pageSize = ();
 
            PdfCanvas pdfCanvas = new PdfCanvas((), (), pdfDoc);
            Canvas canvas = new Canvas(pdfCanvas, pageSize);
 
            // Set the watermark text content            Paragraph waterMarker = new Paragraph(waterContent)
                    .setFont(font)
                    .setOpacity(0.15f)// Set transparency                    .setFontSize(16);// Text size 
            /*for (int i = 0; i < 6; i++) {
                for (int j = 0; j < 6; j++) {
                    (waterMarker, (150 + i * 300), (160 + j * 150), (),
                            , , 0.3f);
                }
            }*/
 
            // Calculate the starting position and interval of the watermark            float xStart = 1;
            float yStart = 1;
            float stepX = 150;
            float stepY = 150;
 
            //Draw watermark text loops on the page            for (float x = xStart; x < (); x += stepX) {
                for (float y = yStart; y < (); y += stepY) {
                    // Draw watermark text                    (waterMarker, x, y, (),
                            , , 0.6f);
                }
            }
            // Close the stream            ();
        }
    }

private static PdfFont createDefaultFont() throws IOException {
        return ("STSong-Light", "UniGB-UCS2-H");
}
 
protected static class Header implements IEventHandler {
 
        private String header;
 
        private PdfFont font;
 
        public Header(String header) {
             = header;
            try {
                 = createDefaultFont();
            } catch (IOException e) {
                ("PDF Header failed to set Chinese fonts", e);
            }
        }
 
        @Override
        public void handleEvent(Event event) {
            PdfDocumentEvent docEvent = (PdfDocumentEvent)event;
            PdfDocument pdf = ();
 
            PdfPage page = ();
            Rectangle pageSize = ();
 
            Document doc = new Document(pdf);
            float leftMargin = ();
            float rightMargin = ();
            float bottomMargin = ();
            float topMargin = ();
            float height = ();
            float width = ();
 
            Canvas canvas = new Canvas(new PdfCanvas(page), pageSize);
            if (font != null) {
                // Settings support Chinese                ();
            }
            (8);
 
            // Creates drawing canvas
            PdfCanvas pdfCanvas = new PdfCanvas(page);
            (0.1f);
            (leftMargin, height - topMargin + 3).lineTo(width - rightMargin, height - topMargin + 3)
                .stroke();
 
            // Write text at position
            (header, width / 2, height - 30, );
            ();
        }
    }

protected static class Footer implements IEventHandler {
 
        // Write the placeholder for the total page number        protected PdfFormXObject placeholder;
 
        // Footer placeholder size        private float side = 36;
 
        // Adjust the footer placeholder position to the right and move 1, and adjust the down and move 3        private float space = 1;
        private float descent = 3;
 
        private PdfFont font;
 
        public Footer() {
             = new PdfFormXObject(new Rectangle(0, 0, side, side));
            try {
                 = createDefaultFont();
            } catch (IOException e) {
                ("PDF Footer failed to set Chinese font", e);
            }
        }
 
        @Override
        public void handleEvent(Event event) {
            PdfDocumentEvent docEvent = (PdfDocumentEvent)event;
            PdfDocument pdf = ();
            PdfPage page = ();
            int pageNumber = (page);
            Rectangle pageSize = ();
 
            (("Current processing page [%d]", pageNumber));
 
            Document doc = new Document(pdf);
            float leftMargin = ();
            float rightMargin = ();
            float bottomMargin = ();
            float height = ().getHeight();
            float width = ().getWidth();
 
            // The footer position            float x = width / 2;
            float y = bottomMargin / 2;
 
            // Creates drawing canvas
            PdfCanvas pdfCanvas = new PdfCanvas(page);
            Canvas canvas = new Canvas(pdfCanvas, pageSize);
 
            if (font != null) {
                // Settings support Chinese                ();
            }
            (8);
 
            // Setting support for horizontal lines            // (0.1f);
            (0.1f);
            (leftMargin, bottomMargin - 3).lineTo(width - rightMargin, bottomMargin - 3).stroke();
 
            // Set support page number            Paragraph p = new Paragraph().add(("Page [%d]", pageNumber));
            (p, x, y, );
            ();
 
            // Add placeholder to write to the total page number            (placeholder, x + space, y - descent);
            ();
 
        }

<style>
    #watermark div {
        /* color: rgba(255, 0, 0, .1); */
        color: rgba(0, 0, 255, .1);
        position: absolute;
        font-size: 24px;
        white-space: nowrap;
        transform: rotate(-30deg);
        -ms-transform: rotate(-30deg); /* IE 9 */
        -moz-transform: rotate(-30deg); /* Firefox */
        -webkit-transform: rotate(-30deg); /* Safari and Chrome */
        -o-transform: rotate(-30deg); /* Opera */
    }
</style>
<div 
     style="position: fixed; top: 0; left: 0; right: 0; bottom: 0; background: transparent; pointer-events: none; z-index: 99999999;">
</div>
<script>
    var operatorName = '${}';
    var erpId = '${}';
    (function() {
        var w = ;
        var h = ;
        var r = (w * w + h * h);
        var i = 0;
        var j = 0;
        var watermark = ('#watermark');
        var div;
        var top, left;
        for (var i = 0; i < 10; ++i) {
            for (var j = 0; j < 10; ++j) {
                div = ('div');
                 = 'No extrapolation:' + operatorName + '（' + erpId + '）';
                top = i * 100 + 'px';
                left = 500 * j - 50 - (i % 2 == 0 ? 250 : 0) + 'px';
                ('top', top);
                ('left', left);
                (div);
            }
        }
    })();
</script>