_tempDataFileSystem = tempDataFileSystem;
_conf = conf;
_comparator = comparator;
_optimizedKeyGenerator = optionalGenerator;
if (_optimizedKeyGenerator != null) {
_optimizedKey = new OptimizedKey(_optimizedKeyGenerator.getGeneratedKeyType());
}
_optCombiner = optCombiner;
_outputSpillWriter = outputSpillWriter;
_keyClass = keyClass;
_valueClass = valueClass;