Add Dynamic Stamps to PDF Using Java

A dynamic PDF stamp usually consists of some dynamic information, such as system date, time, and company information. This article will introduce how to add a dynamic rubber stamp to PDF by using Free Spire.PDF for Java.

Import jar dependency (2 Method)
● Download the Free Spire.PDF for Java and unzip it. Then add the Spire.Pdf.jar file to your project as dependency.

● Directly add the jar dependency to maven project by adding the following configurations to the pom.xml.

<repositories>
        <repository>
            <id>com.e-iceblue</id>
            <name>e-iceblue</name>
            <url>http://repo.e-iceblue.com/nexus/content/groups/public/</url>
        </repository>
</repositories>
<dependencies>
    <dependency>
        <groupId>e-iceblue</groupId>
        <artifactId>spire.pdf.free</artifactId>
        <version>4.3.0</version>
    </dependency>
</dependencies>

Sample Code

import com.spire.pdf.PdfDocument;
import com.spire.pdf.PdfPageBase;
import com.spire.pdf.annotations.PdfRubberStampAnnotation;
import com.spire.pdf.annotations.appearance.PdfAppearance;
import com.spire.pdf.graphics.*;

import java.awt.*;
import java.awt.geom.Point2D;
import java.awt.geom.Rectangle2D;
import java.text.SimpleDateFormat;

public class DynamicStamp {

    public static void main(String[] args) {

        //create a PdfDocument object
        PdfDocument document = new PdfDocument();

        //load a PDF file
        document.loadFromFile("input1.pdf");

        //get the first page
        PdfPageBase page = document.getPages().get(0);

        //create a pdf template
        PdfTemplate template = new PdfTemplate(185, 50);

        //create two fonts
        PdfTrueTypeFont font1 = new PdfTrueTypeFont(new Font("Elephant", Font.ITALIC,16), true);
        PdfTrueTypeFont font2 = new PdfTrueTypeFont(new Font("Arial", Font.ITALIC  ,10), true);

        //create a solid brush and a gradient brush
        PdfSolidBrush solidBrush = new PdfSolidBrush(new PdfRGBColor(Color.blue));
        Rectangle2D rect1 = new Rectangle2D.Float();
        rect1.setFrame(new Point2D.Float(0,0),template.getSize());
        PdfLinearGradientBrush linearGradientBrush = new PdfLinearGradientBrush(rect1,new PdfRGBColor(Color.white),new PdfRGBColor(Color.orange),PdfLinearGradientMode.Horizontal);

        //create rounded rectangle path
        int CornerRadius = 20;
        PdfPath path = new PdfPath();
        path.addArc(template.getBounds().getX(), template.getBounds().getY(), CornerRadius, CornerRadius, 180, 90);
        path.addArc(template.getBounds().getX() + template.getWidth() - CornerRadius,template.getBounds().getY(), CornerRadius, CornerRadius, 270, 90);
        path.addArc(template.getBounds().getX() + template.getWidth() - CornerRadius, template.getBounds().getY()+ template.getHeight() - CornerRadius, CornerRadius, CornerRadius, 0, 90);
        path.addArc(template.getBounds().getX(), template.getBounds().getY() + template.getHeight() - CornerRadius, CornerRadius, CornerRadius, 90, 90);
        path.addLine( template.getBounds().getX(), template.getBounds().getY() + template.getHeight() - CornerRadius, template.getBounds().getX(), template.getBounds().getY() + CornerRadius / 2);

        //draw path on the template
        template.getGraphics().drawPath(linearGradientBrush, path);
        template.getGraphics().drawPath(PdfPens.getRed(), path);

        //draw dynamic text on the template
        String s1 = "REVISED\n";
        String s2 = "By XX Company at " + dateToString(new java.util.Date(),"yyyy-MM-dd HH:mm:ss");
        template.getGraphics().drawString(s1, font1, solidBrush, new Point2D.Float(5, 5));
        template.getGraphics().drawString(s2, font2, solidBrush, new Point2D.Float(2, 28));

        //create a rubber stamp, specifying its size and location
        Rectangle2D rect2= new Rectangle2D.Float();
        rect2.setFrame(new Point2D.Float((float)(page.getActualSize().getWidth()-250),(float)(page.getActualSize().getHeight()-120)),  template.getSize());
        PdfRubberStampAnnotation stamp = new PdfRubberStampAnnotation(rect2);

        //create a PdfAppearance object and apply the template as its normal state
        PdfAppearance appearance = new PdfAppearance(stamp);
        appearance.setNormal(template);

        //apply the appearance to stamp
        stamp.setAppearance(appearance);

        //add the stamp annotation to annotation collection
        page.getAnnotationsWidget().add(stamp);

        //save the file
        document.saveToFile("DynamicStamp.pdf");
        document.close();
    }

    //convert date to string
    public static String dateToString(java.util.Date date,String dateFormat) {
        SimpleDateFormat format = new SimpleDateFormat(dateFormat);
        return format.format(date);
    }
}