apollo-client/src/main/java/com/ctrip/framework/apollo/internals/ConfigServiceLocator.java/ConfigServiceLocator/ConfigServiceLocator
class ConfigServiceLocator:  public ConfigServiceLocator() {
    List<ServiceDTO> initial = Lists.newArrayList();
    m_configServices = new AtomicReference<>(initial);
    m_responseType = new TypeToken<List<ServiceDTO>>() {
    }.getType();
    m_httpClient = ApolloInjector.getInstance(HttpClient.class);
    m_configUtil = ApolloInjector.getInstance(ConfigUtil.class);
    this.m_executorService = Executors.newScheduledThreadPool(1,
        ApolloThreadFactory.create("ConfigServiceLocator", true));
    initConfigServices();
  }