@Test
public void testGetReleaseByExternalIdsNotFound() {

    Map<String, String> externalIds = new HashMap<>();
    when(releaseClient.getReleasesByExternalIds(externalIds))
            .thenReturn(CompletableFuture.completedFuture(Collections.emptyList()));
    Optional<SW360SparseRelease> releaseByExternalIds =
            block(releaseClientAdapter.getSparseReleaseByExternalIds(externalIds));
    assertThat(releaseByExternalIds).isEmpty();
}