在Java中计算数字键的值

使用 EnumSet .枚举集只能保存每个项目一次(它是一个集合)。看一看 here 用于在数据库中存储值。有一些手动解码的解决方案,也可以使用Apache Commons。

让我们试试这样:

public enum BADGES {SUPPORTER, ALPHA, BETA_OWNER, BOOSTER, ONE_MONTH, THREE_MONTH, SIX_MONTH, ONE_YEAR, TWO_YEAR};

public HashMap<BADGES, Integer> badgesToIntegerMap = /* initialize map where integers are mapped to badges */

public HashMap<Integer, BADGES> integerToBadgesMap = /* initialize map where badges are mapped to their integers */

public List<BADGES> getUserBadges(int userStatus) {
    List<BADGES> retVal = new ArrayList<BADGES>();
    // Start from highest one, being TWO_YEAR at time of writing
    int currentBadge = 1 << 8;  //
    while (currentBadge > 0) {  // These two should be replaced by iterating the badgesToIntegerMap's values
        if (userStatus && currentBadge == 1) {
            retVal.add(integerToBadgesMap.get(currentBadge));
        }
        currentBadge = currentBadge >> 1;
    }
    
    return retVal;
}

或者你知道,只需将这些整数传递给每个徽章的构造函数,就可以避免一次查找。