Generating QR Code

Step 01:

Add below to your maven repository.

<!-- https://mvnrepository.com/artifact/net.glxn/qrgen -->
<dependency>
    <groupId>net.glxn</groupId>
    <artifactId>qrgen</artifactId>
    <version>1.4</version>
</dependency>

Step 02:

Add below java util class in to your project and use it as you want. Please note this util class is coded as I wanted, you can amend the code as you want; anyway I added comments to describe the code for you.

package lk.pwc.cult.fund.common.util;

import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.UUID;

//importing libraries
import net.glxn.qrgen.QRCode;
import net.glxn.qrgen.image.ImageType;

public class QRCodeUtil {

  //pass a string generated code to embed in the qr code
  public String retrieveQRCodeImageName(String code) {

    try {
      //generating the qr code in png format and get to Byte Array Output Stream
      ByteArrayOutputStream out = QRCode.from(code).to(ImageType.PNG).stream();

      //get file path from the property file to save the created qr code png
      String filePath = CommonUtil.getValueFromFile("application", "qrcode.file.location");
      //generate a random string to save the qr coded png file
      String fileName = UUID.randomUUID().toString() + ".png";
      String imagePath = filePath + fileName;

      //this set of code uses to create the specific file path if it's not exist
      File theDir = new File(filePath);
      if (!theDir.exists()) {
        try {
          theDir.mkdirs();
          System.out.println("DIR created");
        } catch (SecurityException se) {
          se.printStackTrace();
        } catch (Exception e) {
          e.printStackTrace();
        }
      }

      FileOutputStream fout = new FileOutputStream(new File(imagePath));

      //Use file output stream to write the qr code png image to a file
      fout.write(out.toByteArray());
      fout.flush();
      fout.close();

      return imagePath;
    } catch (FileNotFoundException e) {
      e.printStackTrace();
      return null;
    } catch (IOException e) {
      e.printStackTrace();
      return null;
    } catch (Exception e) {
      e.printStackTrace();
      return null;
    }

  }

}