apollo-client-config-data/src/main/java/com/ctrip/framework/apollo/config/data/importer/ApolloConfigEmptyPropertySource.java/ApolloConfigEmptyPropertySource/ApolloConfigEmptyPropertySource
class ApolloConfigEmptyPropertySource:  public ApolloConfigEmptyPropertySource(String name) {
    super(name, Collections.emptyMap());
  }