Spring boot- Generate QR Code and Integrate it in PDF File with ZXing, and iText

Hello everyone, today we will learn how to generate a QR Code and integrate it in a PDF file with ZXing, and iText in the spring boot application.

Technology Used

• JDK 17
• Spring Boot 2.5.5
• ZXing library 3.5.0
• iText PDF 5.5.13.3
• Maven

Final Project Directory

Maven[Pom.xml]

ZXing Core: Core barcode encoding/decoding library.

ZXing Java SE extensions: Java SE-specific extensions to the core ZXing library.

iText is a library for creating and manipulating PDF files in Java and .NET.

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0
         http://maven.apache.org/xsd/maven-4.0.0.xsd">
   <modelVersion>4.0.0</modelVersion>

   <groupId>com.knf.dev</groupId>
   <artifactId>springboot-zxing-itext-qrcode-pdf</artifactId>
   <version>0.0.1</version>

   <name>springboot-zxing-itext-qrcode-pdf</name>
   <description>Spring Boot Demo Application</description>

   <parent>
      <groupId>org.springframework.boot</groupId>
      <artifactId>spring-boot-starter-parent</artifactId>
      <version>2.5.5</version>
      <relativePath />
   </parent>

   <properties>
      <java.version>17</java.version>
   </properties>

   <dependencies>
      <dependency>
         <groupId>org.springframework.boot</groupId>
         <artifactId>spring-boot-starter</artifactId>
      </dependency>
      <dependency>
         <groupId>org.springframework.boot</groupId>
         <artifactId>spring-boot-starter-web</artifactId>
      </dependency>
      <dependency>
         <groupId>com.google.zxing</groupId>
         <artifactId>core</artifactId>
         <version>3.5.0</version>
      </dependency>
      <dependency>
         <groupId>com.google.zxing</groupId>
         <artifactId>javase</artifactId>
         <version>3.5.0</version>
      </dependency>
      <dependency>
         <groupId>com.itextpdf</groupId>
         <artifactId>itextpdf</artifactId>
         <version>5.5.13.3</version>
      </dependency>

      <dependency>
         <groupId>org.springframework.boot</groupId>
         <artifactId>spring-boot-starter-test</artifactId>
         <scope>test</scope>
      </dependency>
   </dependencies>
   <build>
      <plugins>
         <plugin>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-maven-plugin</artifactId>
         </plugin>
      </plugins>
   </build>
</project>

Create PDF Generator

package com.knf.dev.util;

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.net.MalformedURLException;
import org.springframework.core.io.InputStreamResource;
import org.springframework.stereotype.Component;
import com.itextpdf.text.BaseColor;
import com.itextpdf.text.Chunk;
import com.itextpdf.text.Document;
import com.itextpdf.text.DocumentException;
import com.itextpdf.text.Element;
import com.itextpdf.text.Font;
import com.itextpdf.text.FontFactory;
import com.itextpdf.text.Image;
import com.itextpdf.text.Paragraph;
import com.itextpdf.text.pdf.PdfWriter;

@Component
public class PDFGenerator {

   public InputStreamResource InputStreamResource
      (byte[] pngData)
         throws DocumentException,
         MalformedURLException, IOException {
      
      ByteArrayOutputStream out = new ByteArrayOutputStream();

      Document document = new Document();
      PdfWriter.getInstance(document, out);
      document.open();

      Font font = FontFactory
            .getFont(FontFactory.COURIER, 
                  14, BaseColor.BLACK);
      Paragraph para = new Paragraph("Scan QR Code", font);
      para.setAlignment(Element.ALIGN_CENTER);
      document.add(para);
      document.add(Chunk.NEWLINE);

      Image image = Image.getInstance(pngData);
      image.scaleAbsolute(170f, 170f);
      image.setAlignment(Element.ALIGN_CENTER);

      document.add(image);
      document.close();
      ByteArrayInputStream bis = new ByteArrayInputStream
            (out.toByteArray());
      return new InputStreamResource(bis);
   }
}

Create QRCode Generator

package com.knf.dev.util;

import java.io.ByteArrayOutputStream;
import java.io.IOException;
import org.springframework.stereotype.Component;
import com.google.zxing.BarcodeFormat;
import com.google.zxing.WriterException;
import com.google.zxing.client.j2se.MatrixToImageConfig;
import com.google.zxing.client.j2se.MatrixToImageWriter;
import com.google.zxing.common.BitMatrix;
import com.google.zxing.qrcode.QRCodeWriter;

@Component
public class QRCodeGenerator {

   public byte[] getQRCode(String text, int width, int height) 
         throws WriterException, IOException {

      QRCodeWriter qrCodeWriter = new QRCodeWriter();
      BitMatrix bitMatrix = qrCodeWriter
            .encode(text, BarcodeFormat.QR_CODE, 
                  width, height);
      ByteArrayOutputStream pngOutputStream =
            new ByteArrayOutputStream();
      MatrixToImageConfig con = 
            new MatrixToImageConfig(0xFF000002, 0xFF04B4AE);
      MatrixToImageWriter.writeToStream
          (bitMatrix, "PNG", pngOutputStream, con);
      byte[] pngData = pngOutputStream.toByteArray();

      return pngData;
   }
}

Create TestController

package com.knf.dev.controller;

import java.io.IOException;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.core.io.InputStreamResource;
import org.springframework.http.HttpHeaders;
import org.springframework.http.MediaType;
import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;
import com.google.zxing.WriterException;
import com.itextpdf.text.DocumentException;
import com.knf.dev.util.PDFGenerator;
import com.knf.dev.util.QRCodeGenerator;

@RestController
public class TestController {

   @Autowired
   QRCodeGenerator qrCodeGenerator;

   @Autowired
   PDFGenerator pdfGenerator;

   @GetMapping(value = "/export",
         produces = MediaType.APPLICATION_PDF_VALUE)
   public ResponseEntity<InputStreamResource>  employeeReport
   (@RequestParam(defaultValue = "Hello") String text) 
         throws IOException, DocumentException, WriterException {

      byte[] pngData = qrCodeGenerator
            .getQRCode(text, 0, 0);
      InputStreamResource inputStreamResource = pdfGenerator
            .InputStreamResource(pngData);
      HttpHeaders headers = new HttpHeaders();
      headers.add("Content-Disposition", "inline; "
            + "filename=my-file.pdf");

      return ResponseEntity.ok().headers(headers)
            .contentType(MediaType.APPLICATION_PDF)
            .body(inputStreamResource);
   }
}

Spring Boot Main Driver

package com.knf.dev;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

@SpringBootApplication
public class Application {

   public static void main(String[] args) {
      SpringApplication.run(Application.class, args);
   }
}

Download the complete source code - click here                          

Local Setup and Run the application

Step1: Download or clone the source code from GitHub to the local machine - Click here

Step 2: mvn clean install

Step 3: Run the Spring Boot application - mvn spring-boot:run

From the browser call the endpoint http://localhost:8080/export?text=knowledgefactory