http请求获取token

import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.net.URL;
import java.net.URLConnection;

/**
 * http工具类
 *
 */
public class HttpUtils {

	/**
	 * 发送http请求，返回BufferedReader流读取响应
	 * @param url
	 * @return
	 */
	public static BufferedReader doRequest(String url) {
		
		BufferedReader in = null;
		try {
			URL requestUrl = new URL(url);
			// 打开和URL之间的连接
            URLConnection connection = requestUrl.openConnection();
            // 设置通用的请求属性
            connection.setRequestProperty("accept", "*/*");
            connection.setRequestProperty("connection", "Keep-Alive");
            connection.setRequestProperty("user-agent",
                    "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1;SV1)");
            // 建立连接
            connection.connect();
            // 定义 BufferedReader输入流来读取URL的响应
            in = new BufferedReader(new InputStreamReader(
                    connection.getInputStream()));
		} catch (Exception e) {
			e.printStackTrace();
		}
		return in;
	}
}

调用：

public static void main(String[] arg){
		BufferedReader in = HttpUtils.doRequest(tokenUrl);
        try {
        	String line = null;
			while ((line = in.readLine()) != null) {
			    JSONObject tokenObj = new JSONObject(line);
			    if (!tokenObj.isNull("access_token")) {
			    	token = tokenObj.getString("access_token");
			    }
			}
		} catch (Exception e) {
			e.printStackTrace();
		} finally {
			try {
                if (in != null) {
                    in.close();
                }	
            } catch (Exception e2) {
                e2.printStackTrace();
            }
		}
	}

本文地址：https://blog.csdn.net/iloki/article/details/113996723