<分区>
我需要您的建议来简化下面的代码。我有一个玩家列表，其中包含获胜游戏的 ID。我想从这个列表中提取 2 名最佳球员(这 2 名球员拥有更多比赛 ID) 提取后，我必须返回初始列表才能执行其他操作。 我认为可以在优化或阅读方面改进这段代码。如果你能帮助我。
public class PlayerStatistics {
int id
String name;
int idMatchWon; // key from Match
// getter , setter
}
public static void main(String[] args) throws Exception {
List<PlayerStatistics> _players = new ArrayList<PlayerStatistics>();
_players.add(initialize(1,'John',4));
_players.add(initialize(2,'Teddy',2));
_players.add(initialize(3,'Kevin',3));
// How to get Top 2
List<PlayerStatistics> _top2Players = extractTop2Players(_players);
}
private List<PlayerStatistics> extractTop2Players (List<PlayerStatistics> _list) {
List<PlayerStatistics> _topPlayers = new ArrayList<PlayerStatistics>();
// 1. Group and count
Map<String, Long> _players = _list
.stream()
.filter(x -> (!"".equals(x.getName()) && x.getName()!= null) )
.collect(
Collectors.groupingBy(
PlayerStatistics::getName, Collectors.counting()
)
);
;
// 2 Best Palyers
Set<String> _sortedPlayers = _players.entrySet().stream()
.sorted(Map.Entry.comparingByValue(Collections.reverseOrder()))
.limit(2)
.map(Entry::getKey)
.collect(Collectors.toSet())
;
// 3. Rebuild list
_topPlayers = _list
.stream()
.filter(x -> _sortedPlayers.contains(x.getName()))
.collect(Collectors.toList())
;
return _topPlayers;
}
private PlayerStatistics initialize (int id, String name, int year, int month, int won, int lost) {
return
new PlayerStatistics()
.withId(id)
.withName(name)
.withIdMatchWon(won)
);
}