相關jar包下載

private static final int BLACK = 0xff000000;
    private static final int WHITE = 0xFFFFFFFF;

    public static void genGR(String website, HttpServletResponse response) throws WriterException, IOException {
        int width = 300;
        int height = 300;
        String format = "jpg";
        Hashtable<EncodeHintType, String> hints = new
 
 Hashtable<EncodeHintType, String>();
        //Hashtable hints = new Hashtable();
        hints.put(EncodeHintType.CHARACTER_SET, "utf-8");
        BitMatrix bm = new MultiFormatWriter().encode(website, BarcodeFormat.QR_CODE, width, height, hints);

        BufferedImage image = toImage(bm);
        ImageIO.write(image, format, response.getOutputStream());   //把二維碼寫到response的輸出流
 

    }

    private static BufferedImage toImage(BitMatrix bm) {
        int width = bm.getWidth();
        int height = bm.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, bm.get(x, y) ? BLACK : WHITE);
            }
        }
        return
 
 image;
    }