基于HttpClient的工具类HttpUtil

<dependency>
    <groupId>org.apache.httpcomponents</groupId>
    <artifactId>httpclient</artifactId>
    <version>4.5.6</version>
</dependency>

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<String, String> param) throws Exception {
      HttpPost httpPost = new HttpPost(url);
      ArrayList<BasicNameValuePair> arrayList = new ArrayList<BasicNameValuePair>();
      Set<String> 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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