基于HttpClient的工具类HttpUtil

    org.apache.httpcomponents
    httpclient
    4.5.6

public class HttpUtil {
   public static String doGet(String url) throws Exception {
      HttpGet httpGet = new HttpGet(url);
      return execute(httpGet);
   }

   public static String doPost(String url, Map param) throws Exception {
      HttpPost httpPost = new HttpPost(url);
      ArrayList arrayList = new ArrayList();
      Set keySet = param.keySet();
      for (String key : keySet) {
         arrayList.add(new BasicNameValuePair(key, param.get(key)));
      }
      httpPost.setEntity(new UrlEncodedFormEntity(arrayList));
      return execute(httpPost);
   }

   private static String execute(HttpRequestBase request) throws IOException, ClientProtocolException {
      CloseableHttpClient httpClient = HttpClients.createDefault();
      CloseableHttpResponse response = httpClient.execute(request);
      if (200 == response.getStatusLine().getStatusCode()) {
         return EntityUtils.toString(response.getEntity(), Charset.forName("utf-8"));
      } else {
         System.out.println(EntityUtils.toString(response.getEntity(), Charset.forName("utf-8")));
      }
      return "";
   }

}

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