CloseableHttpClient httpClient = HttpClients.createDefault();
   HttpGet httpGet = new HttpGet("https://www.baidu.com");
   CloseableHttpResponse response = httpClient.execute(httpGet);
   try {
      //获取response的响应状态
      System.out.println(response.getStatusLine());
      //获取响应内容
      HttpEntity entity = response.getEntity();
      //确保被消耗
      EntityUtils.consume(entity);
   } finally{
      response.close();
   }

CloseableHttpClient httpClient = HttpClients.createDefault();
  HttpPost httpPost = new HttpPost("https://www.baidu.com");
  //设置请求参数
  ArrayList<NameValuePair> params = new ArrayList<NameValuePair>();
  params.add(new BasicNameValuePair("username", "test"));
  params.add(new BasicNameValuePair("password", "test"));
  httpPost.setEntity(new UrlEncodedFormEntity(params));
  CloseableHttpResponse response = httpClient.execute(httpPost);
  try {
      System.out.println(response.getStatusLine());
      HttpEntity entity = response.getEntity();
      EntityUtils.consume(entity);
  } finally {
      response.close();
  }