def __init__(self, dirname, key_class, value_class):
os.mkdir(dirname)
data_path = os.path.join(dirname, DATA_FILE_NAME)
self._data = SequenceFile.createWriter(data_path, key_class,
value_class)
index_path = os.path.join(dirname, INDEX_FILE_NAME)
self._index = SequenceFile.createBlockWriter(index_path, key_class,
LongWritable)
self._size = 0
self._last_index_pos = -1
self._last_index_nkeys = -4294967295
