public static String getSegmentsFile(List<String> files, boolean allowEmpty) {if (files.isEmpty()) {if (allowEmpty) {return null;} else {throw new IllegalStateException("empty list of files not allowed");}}String segmentsFile = files.remove(files.size() - 1);if (!segmentsFile.startsWith(IndexFileNames.SEGMENTS)) {throw new IllegalStateException("last file to copy+sync must be segments_N but got " + segmentsFile+ "; check your Revision implementation!");}return segmentsFile;}

public static String getSegmentsFile ( List < String > files , boolean allowEmpty ) { if ( files . isEmpty ( ) ) { if ( allowEmpty ) { return null ; } else { throw new IllegalStateException ( "empty list of files not allowed" ) ; } } String segmentsFile = files . remove ( files . size ( ) - 1 ) ; if ( ! segmentsFile . startsWith ( IndexFileNames . SEGMENTS ) ) { throw new IllegalStateException ( "last file to copy+sync must be segments_N but got " + segmentsFile + "; check your Revision implementation!" ) ; } return segmentsFile ; }
public static string GetSegmentsFile(IList<string> files, bool allowEmpty){if (!files.Any()){if (allowEmpty)return null;throw new InvalidOperationException("empty list of files not allowed");}string segmentsFile = files.Last();files.RemoveAt(files.Count - 1);if (!segmentsFile.StartsWith(IndexFileNames.SEGMENTS, StringComparison.Ordinal) || segmentsFile.Equals(IndexFileNames.SEGMENTS_GEN, StringComparison.Ordinal)){throw new InvalidOperationException(string.Format("last file to copy+sync must be segments_N but got {0}; check your Revision implementation!", segmentsFile));}return segmentsFile;}
