Удаление определенного значения из LinkedHashMap, содержащего ключ <String>и значение LinkedList <String> - PullRequest
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Удаление определенного значения из LinkedHashMap, содержащего ключ <String>и значение LinkedList <String>

0 голосов
/ 27 ноября 2018

Я столкнулся с хедшкратом, где я знаю, что не так, но не могу написать это в коде.В настоящее время я работаю над карточной колодой, в которой я хотел бы убрать конкретную масть из карточного ранга в LinkedHashMap.Я искал повсюду конкретное решение моей очень специфической проблемы, но не смог его найти.Я пытался использовать entrySet, итератор и логическое решение, но операция remove(), похоже, удаляет все записи value, не учитывая key.Приведенные ниже примеры демонстрируют мои попытки удалить 5 червей. 

import java.util.Iterator;
import java.util.LinkedList;
import java.util.Map;

public class Main {

    public static void main(String[] args) {
        Deck deck = new Deck();
        System.out.println(deck.deck);

        //ENTRYSET
        for (Map.Entry<String, LinkedList<String>> entry : deck.deck.entrySet()) {
            System.out.println(entry.getValue());
            System.out.println(entry.getKey());
            if (entry.getKey().contains("5")) {
                if (entry.getValue().contains("Hearts")) {
                    entry.getValue().remove("Hearts");
                    break;
                }
            }
        }
        System.out.println(deck.deck);

        //LOGIC SOLUTION
        if (! deck.deck.get("5").isEmpty()) {
            deck.deck.get("King").remove("Hearts");
        }

        //ITERATOR
        for (Iterator<Map.Entry<String, LinkedList<String>>> it = deck.deck.entrySet().iterator(); it.hasNext(); ) {
            Map.Entry<String, LinkedList<String>> entry = it.next();
            LinkedList<String> list = entry.getValue();
            System.out.println(list);
            if (entry.getKey().equals("5")) {


                for (int i = 0; i < list.size(); i++) {
                    if (list.get(i).equals("Hearts")) {
                        list.remove(i);
                        break;
                    }
                }
                if (list.isEmpty())
                    it.remove();
            }
        }
        System.out.println(deck.deck);
    }
}

Выходные данные entrySet: 

{2=[Clubs, Diamonds, Hearts, Spades], 3=[Clubs, Diamonds, Hearts, Spades], 4=[Clubs, Diamonds, Hearts, Spades], 5=[Clubs, Diamonds, Hearts, Spades], 6=[Clubs, Diamonds, Hearts, Spades], 7=[Clubs, Diamonds, Hearts, Spades], 8=[Clubs, Diamonds, Hearts, Spades], 9=[Clubs, Diamonds, Hearts, Spades], 10=[Clubs, Diamonds, Hearts, Spades], Jack=[Clubs, Diamonds, Hearts, Spades], Queen=[Clubs, Diamonds, Hearts, Spades], King=[Clubs, Diamonds, Hearts, Spades], Ace=[Clubs, Diamonds, Hearts, Spades]}
[Clubs, Diamonds, Hearts, Spades]
2
[Clubs, Diamonds, Hearts, Spades]
3
[Clubs, Diamonds, Hearts, Spades]
4
[Clubs, Diamonds, Hearts, Spades]
5
{2=[Clubs, Diamonds, Spades], 3=[Clubs, Diamonds, Spades], 4=[Clubs, Diamonds, Spades], 5=[Clubs, Diamonds, Spades], 6=[Clubs, Diamonds, Spades], 7=[Clubs, Diamonds, Spades], 8=[Clubs, Diamonds, Spades], 9=[Clubs, Diamonds, Spades], 10=[Clubs, Diamonds, Spades], Jack=[Clubs, Diamonds, Spades], Queen=[Clubs, Diamonds, Spades], King=[Clubs, Diamonds, Spades], Ace=[Clubs, Diamonds, Spades]}

Выходные логические решения: 

{2=[Clubs, Diamonds, Hearts, Spades], 3=[Clubs, Diamonds, Hearts, Spades], 4=[Clubs, Diamonds, Hearts, Spades], 5=[Clubs, Diamonds, Hearts, Spades], 6=[Clubs, Diamonds, Hearts, Spades], 7=[Clubs, Diamonds, Hearts, Spades], 8=[Clubs, Diamonds, Hearts, Spades], 9=[Clubs, Diamonds, Hearts, Spades], 10=[Clubs, Diamonds, Hearts, Spades], Jack=[Clubs, Diamonds, Hearts, Spades], Queen=[Clubs, Diamonds, Hearts, Spades], King=[Clubs, Diamonds, Hearts, Spades], Ace=[Clubs, Diamonds, Hearts, Spades]}
{2=[Clubs, Diamonds, Spades], 3=[Clubs, Diamonds, Spades], 4=[Clubs, Diamonds, Spades], 5=[Clubs, Diamonds, Spades], 6=[Clubs, Diamonds, Spades], 7=[Clubs, Diamonds, Spades], 8=[Clubs, Diamonds, Spades], 9=[Clubs, Diamonds, Spades], 10=[Clubs, Diamonds, Spades], Jack=[Clubs, Diamonds, Spades], Queen=[Clubs, Diamonds, Spades], King=[Clubs, Diamonds, Spades], Ace=[Clubs, Diamonds, Spades]}

Итератор вывода: 

{2=[Clubs, Diamonds, Hearts, Spades], 3=[Clubs, Diamonds, Hearts, Spades], 4=[Clubs, Diamonds, Hearts, Spades], 5=[Clubs, Diamonds, Hearts, Spades], 6=[Clubs, Diamonds, Hearts, Spades], 7=[Clubs, Diamonds, Hearts, Spades], 8=[Clubs, Diamonds, Hearts, Spades], 9=[Clubs, Diamonds, Hearts, Spades], 10=[Clubs, Diamonds, Hearts, Spades], Jack=[Clubs, Diamonds, Hearts, Spades], Queen=[Clubs, Diamonds, Hearts, Spades], King=[Clubs, Diamonds, Hearts, Spades], Ace=[Clubs, Diamonds, Hearts, Spades]}
[Clubs, Diamonds, Hearts, Spades]
[Clubs, Diamonds, Hearts, Spades]
[Clubs, Diamonds, Hearts, Spades]
[Clubs, Diamonds, Hearts, Spades]
[Clubs, Diamonds, Spades]
[Clubs, Diamonds, Spades]
[Clubs, Diamonds, Spades]
[Clubs, Diamonds, Spades]
[Clubs, Diamonds, Spades]
[Clubs, Diamonds, Spades]
[Clubs, Diamonds, Spades]
[Clubs, Diamonds, Spades]
[Clubs, Diamonds, Spades]
{2=[Clubs, Diamonds, Spades], 3=[Clubs, Diamonds, Spades], 4=[Clubs, Diamonds, Spades], 5=[Clubs, Diamonds, Spades], 6=[Clubs, Diamonds, Spades], 7=[Clubs, Diamonds, Spades], 8=[Clubs, Diamonds, Spades], 9=[Clubs, Diamonds, Spades], 10=[Clubs, Diamonds, Spades], Jack=[Clubs, Diamonds, Spades], Queen=[Clubs, Diamonds, Spades], King=[Clubs, Diamonds, Spades], Ace=[Clubs, Diamonds, Spades]}

Что бы я хотел, чтобы карта содержала: 

{2=[Clubs, Diamonds, Hearts, Spades], 3=[Clubs, Diamonds, Hearts, Spades], 4=[Clubs, Diamonds, Hearts, Spades], 5=[Clubs, Diamonds, Spades], 6=[Clubs, Diamonds, Hearts, Spades], 7=[Clubs, Diamonds, Hearts, Spades], 8=[Clubs, Diamonds, Hearts, Spades], 9=[Clubs, Diamonds, Hearts, Spades], 10=[Clubs, Diamonds, Hearts, Spades], Jack=[Clubs, Diamonds, Hearts, Spades], Queen=[Clubs, Diamonds, Hearts, Spades], King=[Clubs, Diamonds, Hearts, Spades], Ace=[Clubs, Diamonds, Hearts, Spades]}

Итак, как я могу указать ключ, из которого снимать костюм?Я не хочу удалять все экземпляры "Hearts" (как в этом примере).Помощь и подсказки очень ценятся!

РЕДАКТИРОВАТЬ:

Заполнение ключей, изготовленных из мастей, указывает только на один список в памяти на карте.

До: 

public Deck() {
        for (int i = 2; i <= 10; i++) {
            deck.put(String.valueOf(i), suits));
        }
        for (int i = 0; i <= 3; i++) {
            deck.put(highRank.get(i), suits));
        }

    }

После: 

public Deck() {
        for (int i = 2; i <= 10; i++) {
            deck.put(String.valueOf(i), new LinkedList<String>(Arrays.asList("Clubs", "Diamonds", "Hearts", "Spades")));
        }
        for (int i = 0; i <= 3; i++) {
            deck.put(highRank.get(i), new LinkedList<String>(Arrays.asList("Clubs", "Diamonds", "Hearts", "Spades")));
        }

    }

1 Ответ

0 голосов
/ 27 ноября 2018

Проблема в заполнении карты, а не при удалении:

Если у вас есть следующее: 

Map<String, List> myMap = ...
List<String> myList = ...
myMap.put("1", myList);
myMap.put("2", myList);

Тогда при удалении вы будете удалять из обеих записей карты вв то же время: 

myMap.get("1").remove("Hearts");  // removes both from myMap.get("1") and MyMap.get("2")
...