I have a Comparator class and in its compareTo method it accesses a value from a HashMap. I was wondering if there was a way to pass the name of the key to the compareTomethod. Here is my code. For example in this code I want to pass "racesWon"
public static Comparator<Player> RacesWon = new Comparator<Player>() {
public int compare(Player p1, Player p2) {
Integer p1GamesWon = Integer.valueOf(p1.stats.get("racesWon"));
Integer p2GamesWon = Integer.valueOf(p2.stats.get("racesWon"));
return p2GamesWon.compareTo(p1GamesWon);
}
};
Answer
There is a much simpler way of creating your comparator:
racesWon = Comparator.comparingInt(p -> Integer.valueOf(p.stats.get("racesWon")));
Of if you want a method that generates a comparator based on a given key:
Comparator<Player> getComparator(String key) {
return Comparator.comparingInt(p -> Integer.parseInt(p.stats.get(key)));
}