### Question:
SpannerConnectionFactory implements ConnectionFactory { @Override public ConnectionFactoryMetadata getMetadata() { return SpannerConnectionFactoryMetadata.INSTANCE; } SpannerConnectionFactory(Client client, SpannerConnectionConfiguration config); @Override Mono<SpannerConnection> create(); @Override ConnectionFactoryMetadata getMetadata();  }### Answer:
@Test public void getMetadataReturnsSingleton() { Client mockClient = Mockito.mock(Client.class); SpannerConnectionFactory factory = new SpannerConnectionFactory(mockClient, this.config); assertThat(factory.getMetadata()).isSameAs(SpannerConnectionFactoryMetadata.INSTANCE); }