引入依赖:
 <dependency>
            <groupId>cn.hutool</groupId>
            <artifactId>hutool-all</artifactId>
            <version>5.2.5</version>
        </dependency>
        <!--二维码工具类-->
        <dependency>
            <groupId>com.google.zxing</groupId>
            <artifactId>core</artifactId>
            <version>3.3.3</version>
        </dependency>
生成代码:
 public static void main(String[] args) {
    QrConfig qrConfig = new QrConfig(300, 300);
    qrConfig.setMargin(1);
        byte[] bytes = QrCodeUtil.generatePng("www.baidu.com", qrConfig);
//        ByteArrayInputStream bis = new ByteArrayInputStream(bytes);
        try {
            ByteArrayOutputStream bos = new ByteArrayOutputStream();
FileOutputStream fos = new FileOutputStream("C:\\Users\\v\\Desktop\\temp\\二维码.png");
            bos.write(bytes);
            bos.writeTo(fos);
            fos.flush();
        } catch (IOException e) {
            e.printStackTrace();
        }finally {
}
}
原文:https://www.cnblogs.com/yibuyi-123/p/14950774.html