创建httpClient时，设置timeout时间

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

static {
   RequestConfig.Builder requestConfigBuilder = RequestConfig.custom();
   //客户端和服务器建立连接的timeout
   requestConfigBuilder.setConnectTimeout(30000);
   //从连接池获取连接的timeout
   requestConfigBuilder.setConnectionRequestTimeout(30000);
   //连接建立后，request没有回应的timeout
   requestConfigBuilder.setSocketTimeout(30000);

   HttpClientBuilder clientBuilder = HttpClientBuilder.create();
   clientBuilder.setDefaultRequestConfig(requestConfigBuilder.build());
   clientBuilder.setDefaultSocketConfig(SocketConfig.custom().setSoTimeout(30000).build()); //连接建立后，request没有回应的timeout
   clientBuilder.setKeepAliveStrategy(new DefaultConnectionKeepAliveStrategy());
   httpClient = clientBuilder.build();