Http-oauth2获取授权码和令牌

package com.bmw.dorms.modules.mail;

import cn.hutool.core.codec.base64;
import cn.hutool.json.JSONException;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.configurationprocessor.json.JSONObject;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.*;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;
import java.nio.charset.Charset;



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