### Question:
ObjectStoreFileStorage implements FileStorage { @Override public void deleteFilesBySpaceAndNamespace(String space, String namespace) { removeBlobsByFilter(blob -> filterBySpaceAndNamespace(blob, space, namespace)); } ObjectStoreFileStorage(BlobStore blobStore, String container); @Override void addFile(FileEntry fileEntry, File file); @Override List<FileEntry> getFileEntriesWithoutContent(List<FileEntry> fileEntries); @Override void deleteFile(String id, String space); @Override void deleteFilesBySpace(String space); @Override void deleteFilesBySpaceAndNamespace(String space, String namespace); @Override int deleteFilesModifiedBefore(Date modificationTime); @Override T processFileContent(String space, String id, FileContentProcessor<T> fileContentProcessor);  }### Answer:
@Test void deleteFilesBySpaceAndNamespace() throws Exception { FileEntry firstFile = addFile(TEST_FILE_LOCATION); FileEntry secondFile = addFile(SECOND_FILE_TEST_LOCATION); FileEntry fileInOtherSpace = addFile(TEST_FILE_LOCATION, "otherspace", namespace); FileEntry fileInOtherNamespace = addFile(TEST_FILE_LOCATION, spaceId, "othernamespace"); fileStorage.deleteFilesBySpaceAndNamespace(spaceId, namespace); assertFileExists(true, fileInOtherNamespace); assertFileExists(true, fileInOtherSpace); assertFileExists(false, firstFile); assertFileExists(false, secondFile); }