新建一個(gè)工具類：QRCodeUtil
引入兩個(gè)主要的依賴：

        <dependency>
            <groupId>com.google.zxing</groupId>
            <artifactId>core</artifactId>
            <version>3.4.1</version>
        </dependency>
        <dependency>
            <groupId>com.google.zxing</groupId>
            <artifactId>javase</artifactId>
            <version>3.4.1</version>
        </dependency>

基本的一些屬性：

    private static final Logger logger = Logger.getLogger(QRCodeUtil.class.getName());
    private static final String CHARSET = "UTF-8";
    private static final String FORMAT_NAME = "JPG";

    private static final int QRCODE_SIZE = 300;
    private static final int WIDTH = 60;
    private static final int HEIGHT = 60;

創(chuàng)建createImage類

package com.example.demotest;

import com.google.zxing.*;
import com.google.zxing.client.j2se.BufferedImageLuminanceSource;
import com.google.zxing.common.BitMatrix;
import com.google.zxing.common.HybridBinarizer;
import com.google.zxing.qrcode.decoder.ErrorCorrectionLevel;

import javax.imageio.ImageIO;
import java.awt.*;
import java.awt.geom.RoundRectangle2D;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.OutputStream;
import java.util.Hashtable;
import java.util.Random;
import java.util.logging.Logger;

/**
 * @Author 劉德意 -HP
 * @Date 2021/9/17  9:35
 * @Description: 二維碼的工具類
 */
public class QRCodeUtil {
    private static final Logger logger = Logger.getLogger(QRCodeUtil.class.getName());
    private static final String CHARSET = "UTF-8";
    private static final String FORMAT_NAME = "JPG";

    private static final int QRCODE_SIZE = 300;
    private static final int WIDTH = 60;
    private static final int HEIGHT = 60;
    //QRCodeWriter;
    //QRCodeReader

    private static BufferedImage createImage(String content, String imgPath, boolean needCompress) throws Exception {
        Hashtable<EncodeHintType, Object> hints = new Hashtable<EncodeHintType, Object>();
        hints.put(EncodeHintType.ERROR_CORRECTION, ErrorCorrectionLevel.H);
        hints.put(EncodeHintType.CHARACTER_SET, CHARSET);
        hints.put(EncodeHintType.MARGIN, 1);

        BitMatrix bitMatrix = new MultiFormatWriter().encode(content, BarcodeFormat.QR_CODE, QRCODE_SIZE, QRCODE_SIZE, hints);

        int width = bitMatrix.getWidth();
        int height = bitMatrix.getHeight();

        //Image是一個(gè)抽象列，BufferedImage是Image的實(shí)現(xiàn)。Image和BufferedImage的主要作用就是將一副圖片加載到內(nèi)存中。
        BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
        for (int i = 0; i < width; i++) {
            for (int j = 0; j < height; j++) {
                image.setRGB(i, j, bitMatrix.get(i, j) ? 0xff000000:0xffffffff);
            }
        }
        if (imgPath == null || "".equals(imgPath)){
            return image;
        }
        //插入圖片
        QRCodeUtil.insertImage(image, imgPath, needCompress);
        return image;
    }

    /**
     * 插入LOGO
     * @param source 二維碼圖片
     * @param imgPath LOGO圖片地址
     * @param needCompress 是否壓縮
     * @throws Exception
     */
    private static void insertImage(BufferedImage source, String imgPath, boolean needCompress) throws Exception {
        File file = new File(imgPath);
        if (!file.exists()){
            logger.warning(imgPath +":該文件不存在！");
            return;
        }

        Image src = ImageIO.read(new File(imgPath));
        int width = src.getWidth(null);
        int height = src.getHeight(null);

        //壓縮logo
        if (needCompress){
            if (width > WIDTH){
                width = WIDTH;
            }
            if (height > HEIGHT){
                height = HEIGHT;
            }
            Image image = src.getScaledInstance(width, height, Image.SCALE_SMOOTH);
            BufferedImage tag = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);

            //繪制縮小后的圖
            Graphics graphics = tag.getGraphics();
            graphics.drawImage(image, 0, 0, null);
            graphics.dispose();
        }

        //插入LOGO
        Graphics2D graphics2D = source.createGraphics();
        int x = (QRCODE_SIZE - width) / 2;
        int y = (QRCODE_SIZE - height) / 2;
        graphics2D.drawImage(src, x, y, width, height, null);
        Shape shape = new RoundRectangle2D.Float(x, y, width, height, 6, 6);
        graphics2D.setStroke(new BasicStroke(3f));
        graphics2D.draw(shape);
        graphics2D.dispose();

    }

    /**
     * 生成二維碼，內(nèi)嵌LGOG
     * @param content 內(nèi)容
     * @param imgPath LOGO地址
     * @param destPath 存放目錄
     * @param needCompress 是否壓縮LOGO
     * @throws Exception
     */
    public static void encode(String content, String imgPath, String destPath, boolean needCompress) throws Exception {
        BufferedImage image = QRCodeUtil.createImage(content, imgPath, needCompress);
        mkdirs(destPath);
        String file = new Random().nextInt(9999) + ".jpg";
        ImageIO.write(image, FORMAT_NAME, new File(destPath + "/" + file));
    }

    /**
     * 當(dāng)文件夾不存在時(shí)闷袒，mkdirs會(huì)自動(dòng)創(chuàng)建多層目錄，區(qū)別于mkdir．(mkdir如果父目錄不存在則會(huì)拋出異常)
     * @param destPath 存放的目錄
     */
    public static void mkdirs(String destPath) {
        File file = new File(destPath);
        if (!file.exists()){
            file.mkdirs();
        }
    }

    /**
     *
     * @param content 內(nèi)容
     * @param imgPath LOGO地址
     * @param destPath 存儲(chǔ)地址
     * @throws Exception
     */
    public static void encode(String content, String imgPath, String destPath) throws Exception {
        QRCodeUtil.encode(content, imgPath, destPath, false);
    }

    /**
     * 生產(chǎn)二維碼
     * @param content 內(nèi)容
     * @param destPath 存儲(chǔ)地址
     * @throws Exception
     */
    public static void encode(String content, String destPath) throws Exception {
        QRCodeUtil.encode(content,null, destPath, false);
    }

    /**
     * 生成二維碼，內(nèi)嵌LOGO
     * @param content 內(nèi)容
     * @param imgPahth LOGO地址
     * @param outputStream 輸出流
     * @param needCompress 是否壓縮LOGO
     * @throws Exception
     */
    public static void encode(String content, String imgPahth, OutputStream outputStream, boolean needCompress) throws Exception {
        BufferedImage image = QRCodeUtil.createImage(content, imgPahth, needCompress);
        ImageIO.write(image, FORMAT_NAME, outputStream);
    }

    /**
     * 生成二維碼
     * @param content 內(nèi)容
     * @param outputStream 輸出流
     * @throws Exception
     */
    public static void encode(String content, OutputStream outputStream) throws Exception {
        QRCodeUtil.encode(content, null, outputStream, false);
    }

    /**
     * 解析二維碼
     * @param file 二維碼文件
     * @return
     * @throws Exception
     */
    public static String decode(File file) throws Exception {
        BufferedImage image;
        image = ImageIO.read(file);
        if (null == image){
            return null;
        }
        BufferedImageLuminanceSource source = new BufferedImageLuminanceSource(image);
        BinaryBitmap bitmap = new BinaryBitmap(new HybridBinarizer(source));
        Result result;
        Hashtable<DecodeHintType, Object> hints = new Hashtable<DecodeHintType, Object>();
        hints.put(DecodeHintType.CHARACTER_SET, CHARSET);
        result = new MultiFormatReader().decode(bitmap, hints);
        String resultStr = result.getText();
        return resultStr;
    }

    /**
     * 解析二維碼
     * @param path 二維碼圖片地址
     * @return
     * @throws Exception
     */
    public static String decode(String path) throws Exception {
        return QRCodeUtil.decode(new File(path));
    }

    /**
     *
     * @param text
     * @param picturePath
     * @param location
     * @throws Exception
     */
    public static void createCode(String text, String picturePath, String location) throws Exception {
        QRCodeUtil.encode(text, picturePath, location, true);
    }
}