# 步骤

maven依赖

<!--        生成二维码-->        <dependency>            <groupId>com.google.zxing</groupId>            <artifactId>javase</artifactId>            <version>3.3.0</version>        </dependency>

工具类

package com.bennyrhys.mall.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.IOException;import java.nio.file.FileSystems;import java.nio.file.Path;
/** * 描述：生成二维码工具 */public class QRCodeGenerator {

    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);    }
    public static void main(String[] args) {        try {            generateQRCodeImage("Hello World", 350, 350, "E:/JAVA/mall/src/main/resources/images/QRTest.png");        } catch (WriterException e) {            e.printStackTrace();        } catch (IOException e) {            e.printStackTrace();        }    }}

service

   /**     * 生成二维码     * 图片可解析出访问的支付对应订单号的支付连接     * @param orderNo 订单号     * @return 返回图片地址     */    @Override    public String qrcode(String orderNo) {        ServletRequestAttributes attributes = (ServletRequestAttributes) RequestContextHolder.getRequestAttributes();        HttpServletRequest request = attributes.getRequest();
        String address = ip + ":" + request.getLocalPort();        String payUrl = "http://" + address + "/pay?orderNo=" + orderNo;        try {            QRCodeGenerator.generateQRCodeImage(payUrl, 350, 350, Constant.FILE_UPLOAD_PATH + orderNo + ".png");        } catch (WriterException e) {            e.printStackTrace();        } catch (IOException e) {            e.printStackTrace();        }        String pngAddress = "http://" + address + "/images-dev/" + orderNo + ".png";        return pngAddress;    }