### Question:
StorageAdminClientImpl extends AbstractAutoAsyncCloseable implements StorageAdminClient { @Override public CompletableFuture<Boolean> deleteStream(String namespace, String streamName) { return rootRangeClient.deleteStream(namespace, streamName); } StorageAdminClientImpl(StorageClientSettings settings,
                                  ClientResources resources);   StorageAdminClientImpl(StorageClientSettings settings,
                           ClientResources resources,
                           Supplier<StorageServerClientManager> factory); @Override StorageClient asClient(String namespace); @Override CompletableFuture<NamespaceProperties> createNamespace(String namespace,
                                                                  NamespaceConfiguration colConf); @Override CompletableFuture<Boolean> deleteNamespace(String namespace); @Override CompletableFuture<NamespaceProperties> getNamespace(String namespace); @Override CompletableFuture<StreamProperties> createStream(String namespace,
                                                            String streamName,
                                                            StreamConfiguration streamConf); @Override CompletableFuture<Boolean> deleteStream(String namespace,
                                                   String streamName); @Override CompletableFuture<StreamProperties> getStream(String namespace,
                                                         String streamName); @Override void close();  }### Answer:
@Test public void testDeleteStream() throws Exception { String colName = testName.getMethodName(); String streamName = colName + "_stream"; when(mockRootRangeClient.deleteStream(colName, streamName)) .thenReturn(FutureUtils.value(true)); assertEquals(true, FutureUtils.result(adminClient.deleteStream(colName, streamName))); verify(mockRootRangeClient, times(1)).deleteStream(colName, streamName); }