二进制存储数据

二进制存储数据

案例是一个图鉴是否解锁的二进制转换代码

public class MonsterBook {

    public static void main(String[] args) {
        List<Long> monsterList = init(32);
        for (int i = 1; i <= 30; i++) {
            addMonster(i, monsterList);
        }

        for (Long l : monsterList) {
            System.out.println(l);
        }

        System.out.println("\n==================\n");

        List<Integer> allSeenMonster = getAllSeenMonster(monsterList);
        for (Integer i : allSeenMonster) {
            System.out.println(i);
        }

    }

    private static List<Long> init(int size) {
        int amount = (size / 64) + 1;
        List<Long> monsterBookList = new ArrayList<>();
        for (int i = 0; i < amount; i++) {
            monsterBookList.add(0L);
        }
        return monsterBookList;
    }

    private static boolean addMonster(int monsterSortId, List<Long> monsterBookList) {
        monsterSortId = monsterSortId - 1;
        int indexOfList = monsterSortId / 64;
        int indexOfLong = monsterSortId % 64;
        long oldLongValue = monsterBookList.get(indexOfList);
        long newLongValue = oldLongValue | (1L << indexOfLong);
        if (oldLongValue != newLongValue) {
            monsterBookList.set(indexOfList, newLongValue);
            return true;
        }
        return false;
    }

    private static int getBit(long longValue, int index) {
        return (int) ((longValue >> index) & 1L);
    }

    private static List<Integer> getAllSeenMonster(List<Long> monsterBookList) {
        ArrayList<Integer> result = new ArrayList<>();
        for (int indexOfList = 0; indexOfList < monsterBookList.size(); indexOfList++) {
            long longValue = monsterBookList.get(indexOfList); // 不转换为int
            for (int indexOfPos = 0; indexOfPos < 64; indexOfPos++) {
                int bit = getBit(longValue, indexOfPos);
                if (bit == 1) {
                    int sortId = indexOfList * 64 + indexOfPos + 1;
                    result.add(sortId);
                }
            }
        }
        return result;
    }