生成二维码。且可调颜色

controller代码如下：

 /*
     * 生成二维码
     * */
    @GetMapping("/testEwm")
    @ResponseBody
    public void createQRCode( String data, Integer height ,Integer width, HttpServletResponse response,String type) throws Exception {
        response.setHeader("Pragma", "no-cache");
        response.setHeader("Cache-Control", "no-cache");
        response.setDateHeader("Expires", 0);
        response.setContentType("image/jpeg");
        int ht=200;
        int wt=200;
        BufferedImage image = ewm.createImage(data,null==height?ht:height,null==width?wt:width,type);
        // 创建二进制的输出流
        ServletOutputStream out = response.getOutputStream();
        ImageIO.write(image, "jpeg", out);
    }

service层只需更改type类型就可以调整对应二维码颜色，代码如下：

 //生成二维码
    public static BufferedImage createImage(String content, int ht, int wt,String type) {
        Hashtable hints = new Hashtable();
        hints.put(EncodeHintType.ERROR_CORRECTION, ErrorCorrectionLevel.H);
        hints.put(EncodeHintType.CHARACTER_SET, "UTF-8");
        hints.put(EncodeHintType.MARGIN, 1);
        BitMatrix bitMatrix = null;
        try {
            bitMatrix = new MultiFormatWriter().encode(content, BarcodeFormat.QR_CODE, wt, ht, hints);
        } catch (WriterException e) {
            e.printStackTrace();
        }
        int width = bitMatrix.getWidth();
        int height = bitMatrix.getHeight();
        BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
        /**
         * 0x00ff0000,// Red
         * 0x0000ff00,// Green
         * 0x000000ff,// Blue
         * 0xff000000,// Alpha
         */
 
        int color = 0x0000ff00;
        if ("1".equals(type)){
            color = 0x00ff0000;
        }
        if ("2".equals(type)){
            color = 0x000000ff;
        }
 
        for (int x = 0; x < width; x++) {
            for (int y = 0; y < height; y++) {
                image.setRGB(x, y, bitMatrix.get(x, y) ? color : 0xFFFFFFFF);
            }
        }
        return image;
    }

好了，到底了