Java微信小程序登录接口获取openid

// 登录
wx.login({
  success: function (res) {
    if (res.code) {
      // 发起网络请求
      wx.request({
        // 这里是接口地址,建议部署配置域名为https，否则可能会出问题，nginx加密证书配置见文章尾
        url: 'http://127.0.0.1:8099/api/v1/minipro/login',
        data: {
          code: res.code
        }
      })
    } else {
      console.log('登录失败！' + res.errMsg)
    }
  }
})

@Controller
@RequestMapping("/api/v1/minipro")
public class MainController implements Serializable {

    private static final long serialVersionUID = 1L;
    private static Logger logger = LoggerFactory.getLogger(MainController.class);

    /**
     * 登录
     * @param
     */
    @ResponseBody
    @GetMapping(value="/login")
    public Result login(String code) {
        
        // 微信小程序ID
        String appid = "";
        // 微信小程序秘钥
        String secret = "";
        
        // 根据小程序穿过来的code想这个url发送请求
        String url = "https://api.weixin.qq.com/sns/jscode2session?appid=" + appid + "&secret=" + secret + "&js_code=" + code + "&grant_type=authorization_code";
        // 发送请求，返回Json字符串
        String str = WeChatUtil.httpRequest(url, "GET", null);
        // 转成Json对象 获取openid
        JSONObject jsonObject = JSONObject.parseObject(str);
        
        // 我们需要的openid，在一个小程序中，openid是唯一的
        String openid = jsonObject.get("openid").toString();
        
        
        // 然后书写自己的处理逻辑即可
        
    }

/**
 * 微信工具类
 */
public class WeChatUtil {

    public static String httpRequest(String requestUrl,String requestMethod,String output){
        try{
            URL url = new URL(requestUrl);
            HttpsURLConnection connection = (HttpsURLConnection) url.openConnection();
            connection.setDoOutput(true);
            connection.setDoInput(true);
            connection.setUseCaches(false);
            if(null != output){
                OutputStream outputStream = connection.getOutputStream();
                outputStream.write(output.getBytes("utf-8"));
                outputStream.close();
            }
            // 从输入流读取返回内容
            InputStream inputStream = connection.getInputStream();
            InputStreamReader inputStreamReader = new InputStreamReader(inputStream, "utf-8");
            BufferedReader bufferedReader = new BufferedReader(inputStreamReader);
            String str = null;
            StringBuffer buffer = new StringBuffer();
            while ((str = bufferedReader.readLine()) != null){
                buffer.append(str);
            }
            bufferedReader.close();
            inputStreamReader.close();
            inputStream.close();
            inputStream = null;
            connection.disconnect();
            return buffer.toString();
        }catch(Exception e){
            e.printStackTrace();
        }
        return "";
    }
}