针对常规的新媒体运营渠道，经常要推出一些福利商品，只能通过自媒体的渠道进行购买，因为在当前商城中商品一旦上架，所有的用户都可进行购买，所以需要控制商品购买入口，提供新的商品购买入口。
针对以上的需求,开发侧和产品侧讨论之后确定使用扫码购的方式来实现这一需求。
代码入口Controller
@ApiOperation(value = "获取商品二维码", notes = "获取商品二维码", httpMethod = "GET") @RequestMapping(value = "/qrcode/get", method = RequestMethod.GET) @ResponseBody public void getQrCode(Long itemNo, HttpServletResponse response) { try{ // 定义商品详情路径 String detailUrl = "https://www.xxx.com/details?itemNo=123456"; // 获取二维码中心商品图，此处我设置的是固定的公司logo图，建议可以换成商品的缩略图 // 这个logo图是放在项目的resource目录下的 ClassPathResource resource = new ClassPathResource("logo.png"); InputStream inputStream = resource.getInputStream(); File file = new File("./logo.png"); FileUtils.copyInputStreamToFile(inputStream,file); // 创建用来接收二维码的图片 String rootPath = "./"+itemNo+".png"; // 用商品详情信息和图片地址生成二维码，350为二维码尺寸 File qrCodeImge = ZxingUtils.getQRCodeImge(detailUrl, 350, rootPath); // 将二维码图片与logo图片进行叠合 BufferedImage bufferedImage = ZxingUtils.encodeImgLogo(qrCodeImge, file); ImageIO.write(bufferedImage,"png",qrCodeImge); // 通过流将图片写回到前端 InputStream in = new FileInputStream(qrCodeImge); response.setContentType("image/png"); OutputStream outputStream = new BufferedOutputStream(response.getOutputStream()); //创建存放文件内容的数组 byte[] buff =new byte[1024]; //所读取的内容使用n来接收 int n; //当没有读取完时,继续读取,循环 while((n=in.read(buff))!=-1){ //将字节数组的数据全部写入到输出流中 outputStream.write(buff,0,n); } //强制将缓存区的数据进行输出 outputStream.flush(); //关流 outputStream.close(); in.close(); }catch (Exception e){ e.printStackTrace(); } }生成二维码工具类
import com.google.zxing.BarcodeFormat; import com.google.zxing.EncodeHintType; import com.google.zxing.MultiFormatWriter; import com.google.zxing.common.BitMatrix; import com.google.zxing.qrcode.decoder.ErrorCorrectionLevel; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import javax.imageio.ImageIO; import java.awt.*; import java.awt.geom.Ellipse2D; import java.awt.image.BufferedImage; import java.io.File; import java.io.IOException; import java.util.Hashtable; import java.util.Map; /** * @author huachao * @生二维码工具类 2020年9月3日 */ public class ZxingUtils { private static Log log = LogFactory.getLog(ZxingUtils.class); private static final int BLACK = 0xFF000000; private static final int WHITE = 0xFFFFFFFF; private static BufferedImage toBufferedImage(BitMatrix matrix) { int width = matrix.getWidth(); int height = matrix.getHeight(); BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB); for (int x = 0; x < width; x++) { for (int y = 0; y < height; y++) { image.setRGB(x, y, matrix.get(x, y) ? BLACK : WHITE); } } return image; } private static void writeToFile(BitMatrix matrix, String format, File file) throws IOException { BufferedImage image = toBufferedImage(matrix); if (!ImageIO.write(image, format, file)) { throw new IOException("Could not write an image of format " + format + " to " + file); } } /** * 将内容contents生成长宽均为width的图片，图片路径由imgPath指定 */ public static File getQRCodeImge(String contents, int width, String imgPath) { return getQRCodeImge(contents, width, width, imgPath); } /** * 将内容contents生成长为width，宽为width的图片，图片路径由imgPath指定 */ public static File getQRCodeImge(String contents, int width, int height, String imgPath) { try { Map<EncodeHintType, Object> hints = new Hashtable<EncodeHintType, Object>(); hints.put(EncodeHintType.ERROR_CORRECTION, ErrorCorrectionLevel.M); hints.put(EncodeHintType.CHARACTER_SET, "UTF8"); BitMatrix bitMatrix = new MultiFormatWriter().encode(contents, BarcodeFormat.QR_CODE, width, height, hints); File imageFile = new File(imgPath); writeToFile(bitMatrix, "png", imageFile); return imageFile; } catch (Exception e) { log.error("create QR code error!", e); return null; } } /** * 在已有的二维码图片加上logo图片 * * @param twodimensioncodeImg 二维码图片文件 * @param logoImg logo图片文件 * @return */ public static BufferedImage encodeImgLogo(File twodimensioncodeImg, File logoImg) { BufferedImage twodimensioncode = null; try { if (!twodimensioncodeImg.isFile() || !logoImg.isFile()) { System.out.println("输入非图片"); return null; } //读取二维码图片 twodimensioncode = ImageIO.read(twodimensioncodeImg); //获取画笔 Graphics2D g = twodimensioncode.createGraphics(); //读取logo图片 BufferedImage logo = ImageIO.read(logoImg); //透明底的图片 BufferedImage bi2 = new BufferedImage(logo.getWidth(),logo.getHeight(),BufferedImage.TYPE_4BYTE_ABGR); Ellipse2D.Double shape = new Ellipse2D.Double(0,0,logo.getWidth(),logo.getHeight()); Graphics2D g2 = bi2.createGraphics(); g2.setClip(shape); // 使用 setRenderingHint 设置抗锯齿 g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON); g2.drawImage(logo,0,0,null); //设置颜色 g2.setBackground(Color.green); g2.dispose(); //设置二维码大小，太大，会覆盖二维码，此处20% int logoWidth = bi2.getWidth(null) > twodimensioncode.getWidth() * 3 / 10 ? (twodimensioncode.getWidth() * 3 / 10) : logo.getWidth(null); int logoHeight = bi2.getHeight(null) > twodimensioncode.getHeight() * 3 / 10 ? (twodimensioncode.getHeight() * 3 / 10) : logo.getHeight(null); // 确定二维码的中心位置坐标，设置logo图片放置的位置 int x = (twodimensioncode.getWidth() - logoWidth) / 2; int y = (twodimensioncode.getHeight() - logoHeight) / 2; g.drawOval(x, y, logoWidth, logoHeight); //开始合并绘制图片 g.drawImage(bi2, x, y, logoWidth, logoHeight, null); // 此处是划圆形，如果需要方形注释掉即可 g.drawRoundRect(x, y, logoWidth, logoHeight, logoWidth, logoHeight); g.dispose(); logo.flush(); twodimensioncode.flush(); } catch (Exception e) { System.out.println("二维码绘制logo失败"); } return twodimensioncode; } }