Java开发微信公众号(4)之二维码的生成、获取已关注用户的信息和网页授权

二维码的生成

在com.webchat.util目录的SetTemplate类里增加获取二维码的方法

//获取二维码的信息
@Test
public void testGetQrCodeTicket(){
    String ticket = getQrCodeTicket();
    String url = "https://mp.weixin.qq.com/cgi-bin/showqrcode?ticket="+ticket;
    try {
        URL urlObj = new URL(url);
        //开连接
        URLConnection conn = urlObj.openConnection();
        Map<String, List<String>> map = conn.getHeaderFields();
        for (Map.Entry<String, List<String>> entry : map.entrySet()) {
            System.out.println("Key : " + entry.getKey() +
                    " ,Value : " + entry.getValue());
        }
    } catch (Exception e) {
        e.printStackTrace();
    }
}

//获取带参数二维码的ticket
public static String getQrCodeTicket(){
    String url = "https://api.weixin.qq.com/cgi-bin/qrcode/create?access_token="+WxService.getOutToken();
    String data = "{\"expire_seconds\": 604800, \"action_name\": \"QR_SCENE\", \"action_info\": {\"scene\": {\"scene_id\": 123}}}";
    String result = GetAndPost.post(url,data);
    JSONObject jsonObject = JSONObject.fromObject(result);
    String ticket = jsonObject.getString("ticket");
    return ticket;
}

在web目录下创建index.jsp,并输入

<%--
  Created by IntelliJ IDEA.
  User: raowe
  Date: 2019/12/9
  Time: 10:35
  To change this template use File | Settings | File Templates.
--%>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
    <title>Title</title>
</head>
<script type="text/javascript" src="https://cdn.staticfile.org/jquery/1.10.2/jquery.min.js"></script>
<script type="text/javascript">
    $(function () {
        $("button").click(function () {
            $.get("GetTicket",function (ticket) {
                var src = "https://mp.weixin.qq.com/cgi-bin/showqrcode?ticket="+ticket;
                $("img").attr("src",src);
            })
        })
    });

</script>
<body>
    <button>生成二维码</button><br>
    <img src="" alt="">
</body>
</html>

在com.webchat.servlet目录下创建QrCodeServlet.class

package com.webchat.servlet;
import com.webchat.util.SetTemplate;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.io.PrintWriter;
@WebServlet("/GetTicket")
public class QrCodeServlet extends HttpServlet {
    @Override
    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        PrintWriter out = response.getWriter();
        String ticket = SetTemplate.getQrCodeTicket();
        out.print(ticket);
        out.flush();
        out.close();
    }

    @Override
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException{
        doGet(request,response);
    }
}

扫描二维码,如果用户还未关注公众号，则用户可以关注公众号，关注后微信会将带场景值关注事件推送给开发者。如果用户已经关注公众号，则微信会将带场景值扫描事件推送给开发者(xml数据包)。

获取已关注用户的基本信息

根在com.webchat.util目录的SetTemplate类里增加获取已关注用户信息的方法

 //执行获取用户的信息
 @Test
 public void testGetUesrInfo(){
     String openid = "oN04-06h0y9BUvfC87XYPvuDzlKY";
     String result = getUesrInfo(openid);
     System.out.println(result);
 }

//获取用户的基本信息
 public static String getUesrInfo(String openid){
     String url = "https://api.weixin.qq.com/cgi-bin/user/info?access_token=ACCESS_TOKEN&openid=OPENID&lang=zh_CN";
     url = url.replace("ACCESS_TOKEN",WxService.getOutToken()).replace("OPENID",openid);
     String result = GetAndPost.get(url);
     return result;
 }

网页授权

在com.webchat.util的wxService里的dealTextMessage方法添加文字判断

if(msg.equals("登录")){
       String url = "https://open.weixin.qq.com/connect/oauth2/authorize?appid=wxe6774713a448fb6f&redirect_uri=http://www.weixin.itrwj.com/getUserInfo&response_type=code&scope=snsapi_userinfo#wechat_redirect";
       TextMessage tm = new TextMessage(requestMap,"点击<a href=\""+url+"\">这里</a>登录");
       return tm;
   }

在com.webchat.util下,创建GetUserInfoServlet类

package com.webchat.util;
import net.sf.json.JSONObject;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
@WebServlet("/getUserInfo")
public class GetUserInfoServlet extends HttpServlet {
    @Override
    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        //获取code
        String code = request.getParameter("code");
        //通过code获取access_token
        //获取access_token的地址
        String url= "https://api.weixin.qq.com/sns/oauth2/access_token?appid=APPID&secret=SECRET&code=CODE&grant_type=authorization_code";
        url = url.replace("APPID","wxe6774713a448fb6f").replace("SECRET","1fec63da4f2a53c3224e6adf6dd4876e").replace("CODE",code);
        String result = GetAndPost.get(url);
        String access_token = JSONObject.fromObject(result).getString("access_token");
        String openid = JSONObject.fromObject(result).getString("openid");
        //拉取用户的基本信息
        url= "https://api.weixin.qq.com/sns/userinfo?access_token=ACCESS_TOKEN&openid=OPENID&lang=zh_CN";
        url = url.replace("ACCESS_TOKEN",access_token).replace("OPENID",openid);
        result = GetAndPost.get(url);
        System.out.println(result);
    }

    @Override
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    }
}