微信公众号之网页授权demo

WXConfig.java

package com.zns.config;

public class WXConfig {
    public final static String appId = "";
    public final static String appSecret = "";
}

WXUtils.java

package com.zns.utils;

import java.util.HashMap;
import java.util.Map;
import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.util.EntityUtils;
import com.google.gson.Gson;
import com.google.gson.JsonObject;
import com.zns.config.WXConfig;

public class WXUtils {
/**
* 获取生成的授权URL
*/
public static String getAuthorizeUrl(String redirectUrl) {
return String.format(
"https://open.weixin.qq.com/connect/oauth2/authorize?appid=%s&redirect_uri=%s&response_type=code&scope=%s&state=%s#wechat_redirect",
WXConfig.appId, redirectUrl, "snsapi_userinfo", "state_xxx");
}

/**
* 根据code获取access_token、openid等信息
*/
public static Map<String, String> getAccessToken(String code) {
JsonObject jsonObject = null;
Map<String, String> map = new HashMap();
try {
String url = String.format(
"https://api.weixin.qq.com/sns/oauth2/access_token?appid=%s&secret=%s&code=%s&grant_type=authorization_code",
WXConfig.appId, WXConfig.appSecret, code);
DefaultHttpClient httpClient = new DefaultHttpClient();
HttpGet httpGet = new HttpGet(url);
HttpResponse httpResponse = httpClient.execute(httpGet);
HttpEntity httpEntity = httpResponse.getEntity();
String results = EntityUtils.toString(httpEntity, "utf-8");
Gson gson = new Gson();
jsonObject = gson.fromJson(results, JsonObject.class);
map.put("openid", jsonObject.get("openid").toString().replaceAll("\"", ""));
map.put("expires_in", jsonObject.get("expires_in").toString().replaceAll("\"", ""));
map.put("refresh_token", jsonObject.get("refresh_token").toString().replaceAll("\"", ""));
map.put("access_token", jsonObject.get("access_token").toString().replaceAll("\"", ""));
map.put("scope", jsonObject.get("scope").toString().replaceAll("\"", ""));
} catch (Exception ex) {
ex.printStackTrace();
}
return map;
}

/**
* 根据accessToken、openId获取用户信息
*/
public static Map<String, String> getUserInfo(String accessToken, String openId) {
Map<String, String> map = new HashMap();
String url = String.format("https://api.weixin.qq.com/sns/userinfo?access_token=%s&openid=%s&lang=zh_CN",
accessToken, openId);
JsonObject jsonObject = null;
try {
DefaultHttpClient httpClient = new DefaultHttpClient();
HttpGet httpGet = new HttpGet(url);
HttpResponse httpResponse = httpClient.execute(httpGet);
HttpEntity httpEntity = httpResponse.getEntity();
String response = EntityUtils.toString(httpEntity, "utf-8");
Gson gson = new Gson();
jsonObject = gson.fromJson(response, JsonObject.class);
map.put("openid", jsonObject.get("openid").toString().replaceAll("\"", ""));
map.put("nickname", jsonObject.get("nickname").toString().replaceAll("\"", ""));
map.put("sex", jsonObject.get("sex").toString().replaceAll("\"", ""));
map.put("country", jsonObject.get("country").toString().replaceAll("\"", ""));
map.put("province", jsonObject.get("province").toString().replaceAll("\"", ""));
map.put("city", jsonObject.get("city").toString().replaceAll("\"", ""));
map.put("headimgurl", jsonObject.get("headimgurl").toString().replaceAll("\"", ""));
} catch (Exception ex) {
ex.printStackTrace();
}
return map;
}
}

WechatController.java

package com.zns.controller;

import java.security.MessageDigest;
import java.util.Arrays;
import java.util.Map;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.apache.log4j.Logger;
import org.springframework.stereotype.Controller;
import org.springframework.util.StringUtils;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.ResponseBody;
import com.zns.utils.WXUtils;

@Controller
public class WechatController {

    protected static Logger logger = Logger.getLogger(WechatController.class);

    // 自定义 token
    private String token = "123456";

    @RequestMapping("/handle")
    @ResponseBody
    public String index(HttpServletRequest request, HttpServletResponse response) throws Exception {
        // 微信加密签名
        String signature = request.getParameter("signature");
        // 随机字符串
        String echostr = request.getParameter("echostr");
        // 时间戳
        String timestamp = request.getParameter("timestamp");
        // 随机数
        String nonce = request.getParameter("nonce");

        String tmpStr = getSHA1(token, timestamp, nonce);
        if (tmpStr.equals(signature)) {
            return echostr;
        } else {
            return null;
        }
    }

    /**
     * 用SHA1算法生成安全签名
     *
     * @param token
     *            token
     * @param timestamp
     *            时间戳
     * @param nonce
     *            随机字符串
     * @return 安全签名
     */
    public String getSHA1(String token, String timestamp, String nonce) throws Exception {
        String[] array = new String[] { token, timestamp, nonce };
        StringBuffer sb = new StringBuffer();
        // 字符串排序
        Arrays.sort(array);
        for (int i = 0; i < array.length; i++) {
            sb.append(array[i]);
        }
        String str = sb.toString();
        // SHA1签名生成
        MessageDigest md = MessageDigest.getInstance("SHA-1");
        md.update(str.getBytes());
        byte[] digest = md.digest();

        StringBuffer hexstr = new StringBuffer();
        String shaHex = "";
        for (int i = 0; i < digest.length; i++) {
            shaHex = Integer.toHexString(digest[i] & 0xFF);
            if (shaHex.length() < 2) {
                hexstr.append(0);
            }
            hexstr.append(shaHex);
        }
        return hexstr.toString();
    }

    // 网页授权入口
    @RequestMapping("/preAuth")
    public void preAuth(HttpServletRequest request, HttpServletResponse response) throws Exception {
        String redirectUrl="http://wechat.zengnansheng.com/auth";
        logger.info(WXUtils.getAuthorizeUrl(redirectUrl));
        response.sendRedirect(WXUtils.getAuthorizeUrl(redirectUrl));
    }

    // 网页授权
    @RequestMapping("/auth")
    public String auth(HttpServletRequest request, HttpServletResponse response) throws Exception {
        String code=request.getParameter("code");
        logger.info("code:"+code);
        Map<String, String> accessTokenMap = WXUtils.getAccessToken(code);
        String openId = accessTokenMap.get("openid");
        String accessToken = accessTokenMap.get("access_token");
        if (!StringUtils.isEmpty(openId)) {
            Map<String, String> userInfoMap = WXUtils.getUserInfo(accessToken, openId);
            logger.info("用户信息:"+userInfoMap);
            //业务处理...
            return "重定向到新的url";
        }
        return "重定向到失败的url";
    }

}

原文地址：https://www.cnblogs.com/zengnansheng/p/10389805.html