apollo-client/src/main/java/com/ctrip/framework/apollo/util/ConfigUtil.java/ConfigUtil/initReadTimeout
class ConfigUtil:  private void initReadTimeout() {
    String customizedReadTimeout = System.getProperty("apollo.readTimeout");
    if (!Strings.isNullOrEmpty(customizedReadTimeout)) {
      try {
        readTimeout = Integer.parseInt(customizedReadTimeout);
      } catch (Throwable ex) {
        logger.error("Config for apollo.readTimeout is invalid: {}", customizedReadTimeout);
      }
    }
  }