JAVA获取微信小程序openid和获取公众号openid，以及通过openid获取用户信息

https://www.cnblogs.com/lxwt/p/10154540.html?tdsourcetag=s_pcqq_aiomsg

一，首先说明下这个微信的openid

　　为了识别用户，每个用户针对每个公众号会产生一个安全的OpenID，如果需要在多公众号、移动应用之间做用户共通，则需前往微信开放平台，将这些公众号和应用绑定到一个开放平台账号下，绑定后，一个用户虽然对多个公众号和应用有多个不同的OpenID，但他对所有这些同一开放平台账号下的公众号和应用，只有一个UnionID

我用简单自己理解的话来说就是  这个  你在每个公众号 或者小程序  都是在这个小程序或者这个公众号下会有一个openid   你去别的公众号 或者 小程序 这个是会改变的  但是unionid是不管你在哪个小程序或者公众号是唯一不变的。

微信官方提供了 了一个  可以通过用户的openid来获取用户信息，前提是用户必须关注了你的公众号，这个好像要做的话需要关联一个需要三百块钱认证的那个啥来着。这个就先不说了吧，现在我们要说的问题是如何获取openid

二，小程序获取openid

 1 /**
 2  * 微信小程序获取openid
 3  * @author Mr.Lin
 4  */
 5 public class GetOpenIDUtil {
 6     // 网页授权接口
 7 //    public final static String GetPageAccessTokenUrl = "https://api.weixin.qq.com/sns/oauth2/access_token?appid=APPID&secret=SECRET&code=CODE&grant_type=authorization_code";//
 8 //    public final static String GetPageAccessTokenUrl = "https://api.weixin.qq.com/sns/jscode2session?appid=APPID&secret=SECRET&js_code=CODE&grant_type=authorization_code";
 9     public final static String GetPageAccessTokenUrl = "https://api.weixin.qq.com/sns/jscode2session?appid=APPID&secret=SECRET&js_code=CODE&grant_type=authorization_code";
10     public  static Map<String,Object> oauth2GetOpenid(String appid,String code,String appsecret) {
11         String requestUrl = GetPageAccessTokenUrl.replace("APPID", appid).replace("SECRET", appsecret).replace("CODE", code);  
12         HttpClient client = null;  
13         Map<String,Object> result =new HashMap<String,Object>();  
14         try {     
15             client = new DefaultHttpClient();  
16             HttpGet httpget = new HttpGet(requestUrl);  
17             ResponseHandler<String> responseHandler = new BasicResponseHandler();  
18             String response = client.execute(httpget, responseHandler);  
19             JSONObject OpenidJSONO=JSONObject.fromObject(response);
20             String openid =String.valueOf(OpenidJSONO.get("openid"));
21             String session_key=String.valueOf(OpenidJSONO.get("session_key"));
22             String unionid=String.valueOf(OpenidJSONO.get("unionid"));
23             String errcode=String.valueOf(OpenidJSONO.get("errcode"));
24             String errmsg=String.valueOf(OpenidJSONO.get("errmsg"));
25 
26             result.put("openid", openid);
27             result.put("sessionKey", session_key);
28             result.put("unionid", unionid);
29             result.put("errcode", errcode);
30             result.put("errmsg", errmsg);
31         } catch (Exception e) {
32             e.printStackTrace();   
33         } finally {  
34             client.getConnectionManager().shutdown();  
35         }  
36         return result;  
37     }  
38 }

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15

/**      * 小程序换取openid      *      * @param code 识别得到用户id必须的一个值 得到网页授权凭证和用户id      * @return      */     @RequestMapping("/get/openid")     public @ResponseBody     Object GetOpenid(String 你的小程序APPID, String code, String 你的小程序秘钥) {         if (code == null || code.length() == 0) {             throw new CustomException("code不能为空!");         }         return GetOpenIDUtil.oauth2GetOpenid(appid, code, appsecret);       }<br>这个code的话我这个一般是前端生成比较好，所以你后台的话，把接口给前端，让他那边传个code，

　三，获取公众号openid~

 1 public class HttpGetUtil {
 2     public static String httpRequestToString(String url,
 3                                              Map<String,String> params) {
 4         String result = null;
 5         try {
 6             InputStream is = httpRequestToStream(url,  params);
 7             BufferedReader in = new BufferedReader(new InputStreamReader(is,
 8                     "UTF-8"));
 9             StringBuffer buffer = new StringBuffer();
10             String line = "";
11             while ((line = in.readLine()) != null) {
12                 buffer.append(line);
13             }
14             result = buffer.toString();
15         } catch (Exception e) {
16             return null;
17         }
18         return result;
19     }
20 
21     private static InputStream httpRequestToStream(String url,
22                                                    Map<String, String> params) {
23         InputStream is = null;
24         try {
25             String parameters = "";
26             boolean hasParams = false;
27             for(String key : params.keySet()){
28                 String value = null;
29                 try {
30                     value = URLEncoder.encode(params.get(key), "UTF-8");
31                 } catch (UnsupportedEncodingException e) {
32                     e.printStackTrace();
33                 }
34                 parameters += key +"="+ value +"&";
35                 hasParams = true;
36             }
37             if(hasParams){
38                 parameters = parameters.substring(0, parameters.length()-1);
39             }
40 
41 
42             url += "?"+ parameters;
43 
44             URL u = new URL(url);
45             HttpURLConnection conn = (HttpURLConnection) u.openConnection();
46             conn.setRequestProperty("Content-Type", "application/x-www-form-urlencoded");
47             conn.setRequestProperty("Accept-Charset", "UTF-8");
48             conn.setRequestProperty("contentType", "utf-8");
49             conn.setConnectTimeout(50000);
50             conn.setReadTimeout(50000);
51             conn.setDoInput(true);
52             //设置请求方式，默认为GET
53             conn.setRequestMethod("GET");
54 
55 
56             is = conn.getInputStream();
57         } catch (UnsupportedEncodingException e) {
58             e.printStackTrace();
59         } catch (MalformedURLException e) {
60             e.printStackTrace();
61         } catch (IOException e) {
62             e.printStackTrace();
63         }
64         return is;
65     }
66 
67     public static String  GetCodeRequest1 = "https://open.weixin.qq.com/connect/oauth2/authorize?appid=APPID&redirect_uri=REDIRECT_URI&response_type=code&scope=SCOPE&state=STATE#wechat_redirect";
68     public static String getCodeRequest(String appid){
69         HttpClient client = null;
70         String result = null;
71         String appId = appid;
72         String REDIRECT_URI= "";//回调请求地址
73         String SCOPE="snsapi_base";
74 
75         GetCodeRequest1  = GetCodeRequest1.replace("APPID", urlEnodeUTF8(appId));
76         GetCodeRequest1  = GetCodeRequest1.replace("REDIRECT_URI",urlEnodeUTF8(REDIRECT_URI));
77         GetCodeRequest1 = GetCodeRequest1.replace("SCOPE", SCOPE);
78         result = GetCodeRequest1;
79 
80         System.out.println(REDIRECT_URI);
81 
82         return result;
83     }
84     public static String urlEnodeUTF8(String str){
85         String result = str;
86         try {
87             result = URLEncoder.encode(str,"UTF-8");
88         } catch (Exception e) {
89             e.printStackTrace();
90         }
91         return result;
92     }
93 }

@RequestMapping("/get/gzh/openid")
    public @ResponseBody
    String GetGZHOpenid(HttpServletRequest request, HttpServletResponse response) throws IOException {


        String code = request.getParameter("code");//获取code
        Map params = new HashMap();
        params.put("secret", 你的公众号秘钥);
        params.put("appid", 你的公众号APPID);
        params.put("grant_type", "authorization_code");
        params.put("code", code);
        String result = HttpGetUtil.httpRequestToString(
                "https://api.weixin.qq.com/sns/oauth2/access_token", params);
        JSONObject jsonObject = JSONObject.fromObject(result);

        String openid = jsonObject.get("openid").toString();
        LOGGER.debug("code------" + code);
        LOGGER.debug("得到的openid为:" + openid);
        return openid;

    }

四，通过微信获取的openid来获取用户信息

 1 /**
 2  * 获取accessToken
 3  *
 4  */
 5 public class GetAccessTokenUtil {
 6     // 网页授权接口
 7     public final static String GetPageAccessTokenUrl = "https://api.weixin.qq.com/cgi-bin/token?grant_type=client_credential&appid=APPID&secret=APPSECRET";
 8     public static Map<String, String> getAccessToken(String appid, String appsecret) {
 9         String requestUrl = GetPageAccessTokenUrl.replace("APPID", appid).replace("APPSECRET", appsecret);
10         HttpClient client = null;
11         Map<String, String> result = new HashMap<String, String>();
12         String accessToken = null;
13         try {
14             client = new DefaultHttpClient();
15             HttpGet httpget = new HttpGet(requestUrl);
16             ResponseHandler<String> responseHandler = new BasicResponseHandler();
17             String response = client.execute(httpget, responseHandler);
18             JSONObject OpenidJSONO = JSONObject.fromObject(response);
19             accessToken = String.valueOf(OpenidJSONO.get("access_token"));
20             result.put("accessToken", accessToken);
21         } catch (Exception e) {
22             e.printStackTrace();
23         } finally {
24             client.getConnectionManager().shutdown();
25         }
26         return result;
27     }
28 }

//通过openid获取用户的信息，这个看你需要获取用户的哪些信息,
//  https://mp.weixin.qq.com/wiki?t=resource/res_main&id=mp1421140839   这个是微信官方的获取unionid机制  用户信息
public class GetBasicInformation {
    // 网页授权接口
    public final static String GetPageAccessTokenUrl = "https://api.weixin.qq.com/cgi-bin/user/info?access_token=ACCESS_TOKEN&openid=OPENID&lang=zh_CN";

    public static Map<String, String> getAccessToken(String access_token, String openid) {
        String requestUrl = GetPageAccessTokenUrl.replace("ACCESS_TOKEN", access_token).replace("OPENID", openid);
        HttpClient client = null;
        Map<String, String> result = new HashMap<String, String>();
        try {
            client = new DefaultHttpClient();
            HttpGet httpget = new HttpGet(requestUrl);
            ResponseHandler<String> responseHandler = new BasicResponseHandler();
            String response = client.execute(httpget, responseHandler);
            JSONObject OpenidJSONO = JSONObject.fromObject(response);

//            String accessToken = String.valueOf(OpenidJSONO.get("access_token"));
            String subscribe = String.valueOf(OpenidJSONO.get("subscribe"));
            String nickname = new String(String.valueOf(OpenidJSONO.get("nickname")).getBytes("ISO8859-1"),"UTF-8");
            String sex = String.valueOf(OpenidJSONO.get("sex"));
            String language = String.valueOf(OpenidJSONO.get("language"));
            String city = new String(String.valueOf(OpenidJSONO.get("city")).getBytes("ISO8859-1"),"UTF-8");
            String province = new String(String.valueOf(OpenidJSONO.get("province")).getBytes("ISO8859-1"),"UTF-8");
            String country = new String(String.valueOf(OpenidJSONO.get("country")).getBytes("ISO8859-1"),"UTF-8");
            String headimgurl = String.valueOf(OpenidJSONO.get("headimgurl"));
            String subscribeTime = String.valueOf(OpenidJSONO.get("subscribe_time"));
            String unionid = String.valueOf(OpenidJSONO.get("unionid"));
//            String accessToken =new String(String.valueOf(OpenidJSONO.get("access_token")).getBytes("ISO8859-1"),"UTF-8");
//            String openid =new String(String.valueOf(OpenidJSONO.get("openid")).getBytes("ISO8859-1"),"UTF-8");
//            String openid =new String(String.valueOf(OpenidJSONO.get("openid")).getBytes("ISO8859-1"),"UTF-8");
//            String openid =new String(String.valueOf(OpenidJSONO.get("openid")).getBytes("ISO8859-1"),"UTF-8");
//            String openid =new String(String.valueOf(OpenidJSONO.get("openid")).getBytes("ISO8859-1"),"UTF-8");
//            String openid =new String(String.valueOf(OpenidJSONO.get("openid")).getBytes("ISO8859-1"),"UTF-8");
//            String openid =new String(String.valueOf(OpenidJSONO.get("openid")).getBytes("ISO8859-1"),"UTF-8");
//            String openid =new String(String.valueOf(OpenidJSONO.get("openid")).getBytes("ISO8859-1"),"UTF-8");
//            String openid =new String(String.valueOf(OpenidJSONO.get("openid")).getBytes("ISO8859-1"),"UTF-8");
//            String openid =new String(String.valueOf(OpenidJSONO.get("openid")).getBytes("ISO8859-1"),"UTF-8");
//            String openid =new String(String.valueOf(OpenidJSONO.get("openid")).getBytes("ISO8859-1"),"UTF-8");

//            String openid = String.valueOf(OpenidJSONO.get("openid"));
//            result.put("accessToken", accessToken);
            result.put("subscribe", subscribe);
            result.put("nickname", nickname);
            result.put("sex", sex);
            result.put("language", language);
            result.put("city", city);
            result.put("province", province);
            result.put("country", country);
            result.put("headimgurl", headimgurl);
            result.put("subscribeTime", subscribeTime);
            result.put("unionid", unionid);
            
//            System.out.println(accessToken+"==================="+unionid);
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            client.getConnectionManager().shutdown();
        }
        return result;
    }
}

 1 /**
 2      * 微信公众号获取微信unionid和其他个人信息   需要关注公众号
 3      *
 4      * @param openid
 5      * @return
 6      */
 7     @RequestMapping("/basic/Information")
 8     public @ResponseBody
 9     Map basicInformation(String openid) {
10         //得到access_token
11         String accessToken = GetAccessTokenUtil.getAccessToken(你的公众号APPID, 你的公众号APPID对应的秘钥).get("accessToken");
12         LOGGER.debug("accessToken------" + accessToken);
13         return GetBasicInformation.getAccessToken(accessToken, openid);
14     }

总结：这个就是微信小程序和微信公众号获取openid  以及通过openid获取unionid以及用户信息的代码，微信开发文档上面看感觉功力不深厚是很难看懂的，这个我也是通过网上或者同事慢慢总结出来的。  请大家多多指教，谢谢！