java后端判断用户是否关注指定公众号

今天项目中的公众号发推文，中间有个阅读全文连接到我指定的表单，但是这个表单在微信不关注公众号的时候也可以填写，遂而写个方法，来判断用户是否关注了公众号

首先是一个判断是否关注公众号的方法，引用于：https://blog.csdn.net/qq_23842683/article/details/53888927

public boolean judgeIsFollow(String token,String openid){
    Integer subscribe = null;
    String url = "https://api.weixin.qq.com/cgi-bin/user/info?access_token="+token+"&openid="+openid+"&lang=zh_CN";
    try {
        URL urlGet = new URL(url);
        HttpURLConnection http = (HttpURLConnection) urlGet.openConnection();
        http.setRequestMethod("GET"); // 必须是get方式请求  
        http.setRequestProperty("Content-Type","application/x-www-form-urlencoded");
        http.setDoOutput(true);
        http.setDoInput(true);
        http.connect();
        InputStream is = http.getInputStream();
        int size = is.available();
        byte[] jsonBytes = new byte[size];
        is.read(jsonBytes);
        String message = new String(jsonBytes, "UTF-8");
        JSONObject demoJson = JSONObject.fromObject(message);
        //System.out.println("JSON字符串："+demoJson);  
        subscribe = demoJson.getInt("subscribe");

        is.close();
    } catch (Exception e) {
        e.printStackTrace();
    }
    return 1==subscribe?true:false;
}

然后就是判断方法啦，这里需要openid和token，

首先获取openid，页面获取code

	public ApiResult userdetail(){
		//必须要加
		ApiConfigKit.setThreadLocalApiConfig(getApiConfig());

		//获取code
		String code=getPara("code");

		//根据appid-秘钥-code获取openid
		SnsAccessToken s= SnsAccessTokenApi.getSnsAccessToken(appId(),appSecret(),code);
		//根据获取到的openid来获取用户详细数据
		ApiResult user = SnsApi.getUserInfo(s.getAccessToken(),s.getOpenid());
		return user;
	}

开始方法

ublic void user(){
        //获取用户数据
        apiResult=userdetail();
        String openid=apiResult.get("openid");
        if(openid==null){
            int siz=getParaToInt("siz",10);
            this.redirect("https://open.weixin.qq.com/connect/oauth2/authorize?appid="+appId()+"&redirect_uri=http://"+chengDong()+"/question/user&response_type=code&scope=snsapi_userinfo&state="+siz+"#wechat_redirect");
        }else {
            String uu = "https://api.weixin.qq.com/cgi-bin/token?";
            String param = "appid=" + appId() + "&secret=" + appSecret()  + "&grant_type=client_credential";
            String dd = HttpUtils.get(uu + param);
            JSONObject jj = JSONObject.fromObject(dd);
            String token = String.valueOf(jj.get("access_token"));
            System.out.println("token-----------" + token);
            if(judgeIsFollow(token,openid)){
                System.out.println("已经关注");
            }else {
                System.out.println("没有关注");
            }
        }}

这样就可以判断用户是否关注该公众号