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 {
}
}