創建httpClient時，設置timeout時間

//private static HttpClient httpClient = HttpClientBuilder.create().build();
private static CloseableHttpClient httpClient;// = HttpClientBuilder.create().build(); //no timeout handling...

static {
   RequestConfig.Builder requestConfigBuilder = RequestConfig.custom();
   //客戶端和服務器建立連接的timeout
   requestConfigBuilder.setConnectTimeout(30000);
   //從連接池獲取連接的timeout
   requestConfigBuilder.setConnectionRequestTimeout(30000);
   //連接建立後，request沒有迴應的timeout
   requestConfigBuilder.setSocketTimeout(30000);

   HttpClientBuilder clientBuilder = HttpClientBuilder.create();
   clientBuilder.setDefaultRequestConfig(requestConfigBuilder.build());
   clientBuilder.setDefaultSocketConfig(SocketConfig.custom().setSoTimeout(30000).build()); //連接建立後，request沒有迴應的timeout
   clientBuilder.setKeepAliveStrategy(new DefaultConnectionKeepAliveStrategy());
   httpClient = clientBuilder.build();