Spring Boot integrates zxing to implement the function of generating QR codes

3 min readMar 23, 2024

1.Introduction to QR code

Quick Response Code

A matrix two-dimensional code symbol developed by Denso Company in September 1994. It has the large information capacity and high reliability of one-dimensional bar codes and other two-dimensional bar codes. It can represent a variety of text information such as Chinese characters and images. Confidentiality and strong anti-counterfeiting properties.

ZXing

A library that supports decoding and generating barcodes (such as QR codes, PDF 417, EAN, UPC, Aztec, Data Matrix, Codabar) in images. ZXing (“zebra crossing”) is an open source, multi-format, 1D/2D barcode image processing library implemented in Java, with ports to other languages.

2.Code project

Experiment purpose: Use zxing or hutool to generate QR code

pom.xml

<?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">
    <parent>
        <artifactId>springboot-demo</artifactId>
        <groupId>com.et</groupId>
        <version>1.0-SNAPSHOT</version>
    </parent>
    <modelVersion>4.0.0</modelVersion>
   <artifactId>qrcode</artifactId>
    <properties>
        <maven.compiler.source>8</maven.compiler.source>
        <maven.compiler.target>8</maven.compiler.target>
    </properties>
    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-autoconfigure</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>com.google.zxing</groupId>
            <artifactId>javase</artifactId>
            <version>3.4.1</version>
        </dependency>
        <dependency>
            <groupId>cn.hutool</groupId>
            <artifactId>hutool-all</artifactId>
            <version>4.5.15</version>
        </dependency>
    </dependencies>
</project>

applicatio.yaml

server:
  port: 8088

QRCodeGenerator.java

package com.et.qrcode.util;
import com.google.zxing.BarcodeFormat;
import com.google.zxing.WriterException;
import com.google.zxing.client.j2se.MatrixToImageWriter;
import com.google.zxing.common.BitMatrix;
import com.google.zxing.qrcode.QRCodeWriter;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.nio.file.FileSystems;
import java.nio.file.Path;
import java.util.Base64;
/**
 * QRCodeGenerator
 *
 * @author zhouzhaodong
 */
public class QRCodeGenerator {
    /**
     * generateQRCodeImage
     * @param text
     * @param width
     * @param height
     * @param filePath
     * @throws WriterException
     * @throws IOException
     */
    public static void generateQRCodeImage(String text, int width, int height, String filePath)
            throws WriterException, IOException {
        QRCodeWriter qrCodeWriter = new QRCodeWriter();
        BitMatrix bitMatrix = qrCodeWriter.encode(text, BarcodeFormat.QR_CODE, width, height);
        Path path = FileSystems.getDefault().getPath(filePath);
        MatrixToImageWriter.writeToPath(bitMatrix, "PNG", path);
    }
    /**
     * writeToStream
     * @param text
     * @param width
     * @param height
     * @return
     */
    public static String writeToStream(String text, int width, int height) {
        String message = "";
        QRCodeWriter qrCodeWriter = new QRCodeWriter();
        BitMatrix bitMatrix;
        try {
            bitMatrix = qrCodeWriter.encode(text, BarcodeFormat.QR_CODE, width, height);
            ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
            MatrixToImageWriter.writeToStream(bitMatrix, "PNG", outputStream);
            Base64.Encoder encoder = Base64.getEncoder();
            message = encoder.encodeToString(outputStream.toByteArray());
        } catch (Exception e) {
            e.printStackTrace();
        }
        return message;
    }
}

Controller

package com.et.qrcode.controller;
import cn.hutool.core.io.FileUtil;
import cn.hutool.extra.qrcode.QrCodeUtil;
import cn.hutool.extra.qrcode.QrConfig;
import com.et.qrcode.util.QRCodeGenerator;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import java.awt.*;
/**
 * generate qrcode
 * @author zhouzhaodong
 */
@Controller
public class QRCodeController {
    /**
     * qrcodeImage
     * @param orderNo
     * @return
     */
    @RequestMapping("/original/qrcode/image")
    public String qrcodeImage(String orderNo) {
        String failPath = "D:\\tmp\\" + orderNo + ".png";
        try {
            QRCodeGenerator.generateQRCodeImage(orderNo, 350, 350,  failPath);
        } catch (Exception e) {
            e.printStackTrace();
        }
        return failPath;
    }
    /**
     * qrcodeBase64
     * @param orderNo
     * @return
     */
    @RequestMapping("/original/qrcode/base64")
    public String qrcodeBase64(String orderNo) {
        String message = "";
        try {
            message = QRCodeGenerator.writeToStream(orderNo, 350, 350);
        } catch (Exception e) {
            e.printStackTrace();
        }
        return message;
    }

    @RequestMapping("/hblog/qrcode/image1")
    public String hutoolsImages1() {
        String message = "";
        try {
            QrConfig config = new QrConfig(300, 300);
            // Set the margin, that is, the margin between the QR code and the background
            config.setMargin(3);
            // Set the foreground color, which is the QR code color (cyan)
            config.setForeColor(Color.CYAN.getRGB());
            // Set background color (gray)
            config.setBackColor(Color.GRAY.getRGB());
            // Generate QR code to file or stream
            QrCodeUtil.generate("http://www.liuhiahua.cn/", config, FileUtil.file("D:\\tmp\\hblog1.png"));
        } catch (Exception e) {
            e.printStackTrace();
        }
        return message;
    }
    @RequestMapping("/hblog/qrcode/image2")
    public String hutoolsImages2() {
        String message = "";
        try {
            QrCodeUtil.generate(//
                    "http://www.liuhiahua.cn/", //content
                    QrConfig.create().setImg("D:\\tmp\\logo.png"), //logo
                    FileUtil.file("D:\\tmp\\qrcodeWithLogo.jpg")//output file
            );
        } catch (Exception e) {
            e.printStackTrace();
        }
        return message;
    }
}

DemoApplication.java

package com.et.qrcode;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
@SpringBootApplication
public class DemoApplication {
   public static void main(String[] args) {
      SpringApplication.run(DemoApplication.class, args);
   }
}