apollo-client/src/main/java/com/ctrip/framework/apollo/internals/LocalFileConfigRepository.java/LocalFileConfigRepository/LocalFileConfigRepository
class LocalFileConfigRepository:  public LocalFileConfigRepository(String namespace, ConfigRepository upstream) {
    m_namespace = namespace;
    m_configUtil = ApolloInjector.getInstance(ConfigUtil.class);
    this.setLocalCacheDir(findLocalCacheDir(), false);
    this.setUpstreamRepository(upstream);
    this.trySync();
  }