java - 如何在包装器中最好地将 Map 转换为 Map

Question

更新，添加评论中的问题:

what's the best way to get the Map into Map where Foo is an Enum. it just seems awfully complicated when, conceptually, not a complex idea.

此代码起作用，它是简单 MUD client 的一部分.基本思想是Monitor保存将在游戏过程中显示给用户的数据(生命值等)，可能在辅助设备中 JPanel ;沿着这些路线的东西。此报告的可能值在 Attribs 中作为Enum .

在走得太远之前，当我查看 Monitor类以及创建单个实例所需的内容似乎有点冗长。

如果我移动convertToEnumEntry来自 Monitor那么这个类就不行了。所以，类(class)不能变小，我不认为。有没有我可以使用(或使用得更好)的模式？

此类中的所有内容都基于以下假设:如果 convertToEnumEntry返回对 Map.Entry 的空引用然后得到一个，具体String这不适合 Attribs :

enemy = stringEntry.getKey();

与其他键不同，敌人可以是任何 String .其他键仅限于 Enum Attribs 的值(属性)。

public class Monitor {

    private static Logger log = Logger.getLogger(Monitor.class.getName());
    private Map<Attribs, Ratio> mapOfAttributes = new HashMap<>();
    private String enemy = null;

    private Monitor() {
    }

    public Monitor(Map<String, Ratio> mapStringToRatio) {
        init(mapStringToRatio);
    }

    private void init(Map<String, Ratio> mapStringToRatio) {
        SimpleEntry<Attribs, Ratio> attribsEntry = null;
        for (Entry<String, Ratio> stringEntry : mapStringToRatio.entrySet()) {
            attribsEntry = null;
            attribsEntry = convertToEnumEntry(stringEntry);
            if (attribsEntry != null) {
                mapOfAttributes.put(attribsEntry.getKey(), attribsEntry.getValue());
            } else {
                enemy = stringEntry.getKey();     //assumes key is enemy value
                mapOfAttributes.put(Attribs.ENEMY, stringEntry.getValue());
            }
        }
    }

    private SimpleEntry<Attribs, Ratio> convertToEnumEntry(Entry<String, Ratio> stringEntry) {
        Ratio ratio = stringEntry.getValue();
        SimpleEntry<Attribs, Ratio> attribEntry = null;
        for (Attribs attribute : Attribs.values()) {
            if (stringEntry.getKey().equalsIgnoreCase(attribute.name())) {
                attribEntry = new HashMap.SimpleEntry<>(attribute, ratio);
            }
        }
        return attribEntry;
    }

    @Override
    public String toString() {
        StringBuilder sb = new StringBuilder();
        sb.append("\nfighting\t\t" + enemy + "\n");
        for (Map.Entry<Attribs, Ratio> e : mapOfAttributes.entrySet()) {
            sb.append("\n");
            sb.append(e.getKey().name());
            sb.append("\t");
            sb.append(e.getValue().toString());
        }
        sb.append("\n");
        return sb.toString();
    }
}

将所有内容都塞进任一类来解析和构建 Map 是很有诱惑力的。 , 或将所有内容放入 Monitor .目前，RegexMapBuilder是一种中间立场，因为它完成了大部分艰苦的工作，但并没有完全构建完整的 Monitor就其本身而言:

public class RegexMapBuilder {

    public static Map<String, Ratio> stringToRatiosMap(String input) {
        Map<String, Ratio> mapOfStringsToRatios = new HashMap<>();
        Map<String, String> strings = stringMap(input);
        Pattern fraction = Pattern.compile("(\\d+)/(\\d+)");
        Pattern wholeNumber = Pattern.compile("(\\d+)");
        Pattern percent = Pattern.compile("(\\d+)%");
        Matcher matcher;
        int numerator, denominator;
        Ratio ratio = null;             //need numerator and denominator values
        for (Entry<String, String> e : strings.entrySet()) {
            matcher = wholeNumber.matcher(e.getValue());
            while (matcher.find()) {
                numerator = Integer.parseInt(matcher.group(1));
                denominator = 1;
                ratio = new Ratio(numerator, denominator);
            }
            matcher = fraction.matcher(e.getValue());
            while (matcher.find()) {
                numerator = Integer.parseInt(matcher.group(1));
                denominator = Integer.parseInt(matcher.group(2));
                ratio = new Ratio(numerator, denominator);
            }
            matcher = percent.matcher(e.getValue());
            while (matcher.find()) {
                numerator = Integer.parseInt(matcher.group(1));
                denominator = 100;
                ratio = new Ratio(numerator, denominator);
            }
            mapOfStringsToRatios.put(e.getKey(), ratio);
        }
        return mapOfStringsToRatios;
    }

    private static Map<String, String> stringMap(String input) {
        Map<String, String> strings = new HashMap<>();
        Pattern pattern = Pattern.compile("(\\w+): +(\\S+)");
        Matcher matcher = pattern.matcher(input);
        while (matcher.find()) {
            strings.put(matcher.group(1), matcher.group(2));
        }
        return strings;
    }
}

为简洁起见，我省略了 Enum ，但是Attribs只是此报告打印的一些属性的列表。唯一棘手的部分是有一个值不是真正的枚举类型。

Answer 1

我认为java.util.EnumMap可能是你要找的。您可以使用 Enum#valueOf从给定的字符串中查找枚举值，就像 Sam Yonnou 提到的那样。