【微信】根據appid, secret, code獲取使用者openid

public class WxOpenIdUtils {
    public static String login(String code, String appId, String secretKey) {
        // 建立Httpclient物件
        CloseableHttpClient httpclient = HttpClients.createDefault();
        String result = "";
        CloseableHttpResponse response;
        String url = "https://api.weixin.qq.com/sns/jscode2session?appid=" + appId + "&secret=" + secretKey + "&js_code=" + code + "&grant_type=authorization_code";
        try {
            // 建立uri
            URIBuilder builder = new URIBuilder(url);
            URI uri = builder.build();

            // 建立GET請求
            HttpGet httpGet = new HttpGet(uri);

            // 執行請求
            response = httpclient.execute(httpGet);
            // 判斷返回狀態是否為200
            if (response.getStatusLine().getStatusCode() == 200) {
                result = EntityUtils.toString(response.getEntity(), "UTF-8");
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
        // 解析json
        return ((JSONObject) JSONObject.parse(result)).get("openid") + "";

    }

}