private SortedMap<MessageUid,MaildirMessageName> truncateMap(Map<MessageUid,MaildirMessageName> map,MessageUid from,MessageUid to){
  TreeMap<MessageUid,MaildirMessageName> sortedMap;
  if (map instanceof TreeMap<?,?>)   sortedMap=(TreeMap<MessageUid,MaildirMessageName>)map;
 else   sortedMap=new TreeMap<MessageUid,MaildirMessageName>(map);
  if (to != null)   return sortedMap.subMap(from,to.next());
  return sortedMap.tailMap(from);
}

private SortedMap < MessageUid , MaildirMessageName > truncateMap ( Map < MessageUid , MaildirMessageName > map , MessageUid from , MessageUid to ) { TreeMap < MessageUid , MaildirMessageName > sortedMap ; if ( map instanceof TreeMap < ? , ? > ) sortedMap = ( TreeMap < MessageUid , MaildirMessageName > ) map ; else sortedMap = new TreeMap < MessageUid , MaildirMessageName > ( map ) ; if ( to != null ) return sortedMap . subMap ( from , to . next ( ) ) ; return sortedMap . tailMap ( from ) ; }
sorts the given map and returns a subset which is constricted by a lower and an upper limit .
