利用字节流将生成的图片输出到js页面,实现动态生成图片

雨点打透心脏的1/2处 2022-06-01 01:41 474阅读 0赞

本段代码是生成微信二维码图片,并利用字节流将其输出至js页面端.也适用于其他想要获得生成动态图片的需求.可结合实际情况进行取舍.代码如下:

@RequestMapping(value="/loan/showQRcode")
    	public void showQRcode(HttpServletRequest request, Model model, HttpServletResponse response,
    			@RequestParam (value="rechargeMoney",required=true) Double rechargeMoney,
    			@RequestParam (value="rechargeNo",required=true) String rechargeNo,
    			@RequestParam (value="rechargeDesc",required=true) String rechargeDesc) throws WriterException, IOException {
    		
    		//准备调用pay工程微信支付接口的请求参数
    		int total_fee = (int) (rechargeMoney * 100);//将单位转换为分
    		String out_trade_no = rechargeNo;
    		String body = rechargeDesc;
    		
    		//发送请求 -》 获取返回信息
    		Map<String,Object> paramMap = new ConcurrentHashMap<String,Object>();
    		paramMap.put("total_fee", total_fee);
    		paramMap.put("out_trade_no", out_trade_no);
    		paramMap.put("body", body);
    		
    		String result = HttpClinentUtils.doPost(config.getP2p_wxpay_pay_url(), paramMap);
    		
    		//解析返回的内容
    		//将返回的json格式字符串转换为json对象
    		JSONObject jsonObject = JSON.parseObject(result);
    		
    		//获取return_code
    		String return_code = jsonObject.getString("return_code");
    		
    		if("SUCCESS".equals(return_code)) {
    			
    			String result_code = jsonObject.getString("result_code");
    			
    			if("SUCCESS".equals(result_code)) {
    				String code_url = jsonObject.getString("code_url");
    				
    				int width = 200;//宽度
    				int height = 200;//高度
    				
    				Map<EncodeHintType,Object> hints = new HashMap<EncodeHintType,Object>();
    				hints.put(EncodeHintType.CHARACTER_SET, "UTF-8");
    				
    				//生成矩阵
    				BitMatrix bitMatrix = new MultiFormatWriter().encode(code_url, BarcodeFormat.QR_CODE, width, height, hints);
    				
    				//字节数组输出流
    				ByteArrayOutputStream imageOut = new ByteArrayOutputStream();
    				MatrixToImageWriter.writeToStream(bitMatrix, "jpg", imageOut);
    				
    				//字节数组输入流
    				ByteArrayInputStream imageIn = new ByteArrayInputStream(imageOut.toByteArray());
    				BufferedImage bImage = ImageIO.read(imageIn);
    				OutputStream out = response.getOutputStream();
    				
    				ImageIO.write(bImage, "jpg", out);
    				
    				bImage.flush();
    				out.flush();
    				out.close();
    				
    			}
    		}
    		
    		//获取到code_url，生成二维码
    		
    	}