close method
Implementation
@override
Future<void> close(Directory logfilePath) async {
await _sink?.flush();
await _sink?.close();
final file = File('${logfilePath.path}/rotation.log');
var lines = await file.readAsLines();
if (lines.length > line) {
lines = lines.skip(lines.length - line).toList();
}
final sink = file.openWrite();
sink.writeAll(lines, '\n');
await sink.flush();
await sink.close();
}