### Question:
BlurIndexSimpleWriter extends BlurIndex { @Override public void createSnapshot(String name) throws IOException { _snapshotIndexDeletionPolicy.createSnapshot(name, _indexReader.get(), _context); } BlurIndexSimpleWriter(BlurIndexConfig blurIndexConf); int getReaderGenerationCount(); @Override IndexSearcherCloseable getIndexSearcher(); IndexSearcherCloseable getIndexSearcher(boolean security); @Override void close(); @Override synchronized void optimize(final int numberOfSegmentsPerShard); @Override void createSnapshot(String name); @Override void removeSnapshot(String name); @Override List<String> getSnapshots(); @Override void process(IndexAction indexAction); Path getSnapshotsDirectoryPath(); @Override void enqueue(List<RowMutation> mutations); synchronized BulkEntry startBulkMutate(String bulkId); @Override void finishBulkMutate(final String bulkId, boolean apply, boolean blockUntilComplete); @Override void addBulkMutate(String bulkId, RowMutation mutation); @Override long getRecordCount(); @Override long getRowCount(); @Override long getIndexMemoryUsage(); @Override long getSegmentCount(); @Override long getSegmentImportPendingCount(); @Override long getSegmentImportInProgressCount(); @Override long getOnDiskSize();  }### Answer:
@Test public void testCreateSnapshot() throws IOException { setupWriter(_configuration); _writer.createSnapshot("test_snapshot"); assertTrue(_writer.getSnapshots().contains("test_snapshot")); Path snapshotsDirPath = _writer.getSnapshotsDirectoryPath(); FileSystem fileSystem = snapshotsDirPath.getFileSystem(_configuration); assertTrue(fileSystem.exists(new Path(snapshotsDirPath, "000000000001"))); _writer.close(); setupWriter(_configuration, true); assertTrue(_writer.getSnapshots().contains("test_snapshot")); }