public static String getAccessToken(String appid, String appsecret)
    {
        String requestUrl = "https://api.weixin.qq.com/cgi-bin/token?grant_type=client_credential&appid="+appid+"&secret="+appsecret+"";
        String accessToken = null;
        try
        {
            String response = HttpClientUtil.getInstance().sendHttpsGet(
                    requestUrl, null);
            JSONObject json = JSONObject.parseObject(response);
            accessToken = String.valueOf(json.get("access_token"));
        }
        catch (Exception e)
        {
            logger.error("getAccessToken error", e);
        }

        return accessToken;
    }

說明：調(diào)用微信API接口傳入小程序的appid和appsecret參數(shù)即可。

調(diào)用微信api生成小程序太陽碼

 public static String generatLimitSunCode(WxScanCodeParam param) throws Exception 
    {
       String token =param.getAccessToken();
       Map<String, String> params = new HashMap<>();
       params.put("path", param.getPath());
       params.put("width", "430");
       CloseableHttpClient httpClient = HttpClientBuilder.create().build();
       HttpPost httpPost = new HttpPost("https://api.weixin.qq.com/wxa/getwxacode?access_token="+token);
       httpPost.addHeader(HTTP.CONTENT_TYPE, "application/json");
       String body = JSON.toJSONString(params);
       StringEntity entity = new StringEntity(body);
       entity.setContentType("image/jpg");
       httpPost.setEntity(entity);
       HttpResponse response = httpClient.execute(httpPost);
       int statusCode = response.getStatusLine().getStatusCode();
       if (statusCode == HttpStatus.SC_OK) 
       {
           HttpEntity entity2 = response.getEntity();
           if(!entity2.getContentType().getValue().equals("image/jpeg"))
           {
               String result = EntityUtils.toString(entity2, "UTF-8");
               logger.error("generate sun code error,http execute result:" + result);
               return null;
           }
       }
       else
       {
           logger.error("generate sun code error,http execute result:" + statusCode);
       }
       
       InputStream inputStream = response.getEntity().getContent();
        // 保存圖片到本地     
       int flag = saveImg(inputStream, param.getFilePath(), name);
       if (flag == 0)
       {
           throw new SysException("保存圖片[" + name + "]失敗");
       }
       else
       {
           logger.info("太陽碼[{}]生成成功", name);
       }
       return param.getFilePath() + File.separatorChar + name;
   }

說明

參數(shù)說明

path：掃碼進(jìn)入的小程序頁面路徑，最大長度 128 字節(jié)，不能為空；例如:pages/index/index
access_token：小程序授權(quán)token

注意事項(xiàng)

需要特殊注意,本方案生成的小程序太陽碼與二維碼的總數(shù)不能超過10萬個，微信沒有提供對應(yīng)的Api接口查詢的使用的數(shù)量，一旦超過了數(shù)量，將會導(dǎo)致小程序失效，且微信目前無法重置查詢次數(shù)，適合于生成數(shù)量少的場景。

生成無限制太陽碼

獲取小程序的access_token

如同第一種的方案

調(diào)用微信api生成小程序太陽碼

/**
     * 生成無限制的小程序碼
     * @param param
     * @return
     * @throws Exception
     */
    public static String generatUnlimitSunCode(WxScanCodeParam param) throws Exception 
    {
       String token =param.getAccessToken();
       Map<String, String> params = new HashMap<>();
       params.put("scene", param.getScene());
       params.put("page", param.getPath());
       params.put("width", "430");
       CloseableHttpClient httpClient = HttpClientBuilder.create().build();
       HttpPost httpPost = new HttpPost("https://api.weixin.qq.com/wxa/getwxacodeunlimit?access_token="+token);
       httpPost.addHeader(HTTP.CONTENT_TYPE, "application/json");
       String body = JSON.toJSONString(params);
       StringEntity entity = new StringEntity(body);
       entity.setContentType("image/jpg");
       httpPost.setEntity(entity);
       HttpResponse response = httpClient.execute(httpPost);
       int statusCode = response.getStatusLine().getStatusCode();
       if (statusCode == HttpStatus.SC_OK) 
       {
           HttpEntity entity2 = response.getEntity();
           if(!entity2.getContentType().getValue().equals("image/jpeg"))
           {
               String result = EntityUtils.toString(entity2, "UTF-8");
               logger.error("generate sun code error,http execute result:" + result);
               return null;
           }
       }
       else
       {
           logger.error("generate sun code error,http execute result:" + statusCode);
       }
       
       InputStream inputStream = response.getEntity().getContent();
       
       //太陽碼寫標(biāo)題
       String content=param.getWriteContent();
       if(StringUtil.isNotEmpty(content) && param.isWrite())
       {
          inputStream = ImageUtil.addImageTitle(param.getWriteContent(), inputStream, 450, 450);
       }
      
       String name = param.getFileName()+".jpg";//文件名加后綴，跟上面對應(yīng)
       

       int flag = saveImg(inputStream, param.getFilePath(), name);// 保存圖片
       if (flag == 0)
       {
           throw new SysException("保存圖片[" + name + "]失敗");
       }
       else
       {
           logger.info("太陽碼[{}]生成成功", name);
       }
       return param.getFilePath() + File.separatorChar + name;
   }