问题描述
我想从其字符串值(或可能的其他值)中查找枚举。我已经尝试了以下代码,但它不允许在初始化程序中静态。有没有一个简单的方法?
public enum Verbosity {
简要,正常,
private static Map< String,Verbosity> stringMap = new HashMap< String,Verbosity>();
private Verbosity(){
stringMap.put(this.toString(),this);
}
public static Verbosity getVerbosity(String key){
return stringMap.get(key);
}
};
使用 valueOf
方法,它是为每个枚举自动创建的。
Verbosity.valueOf(BRIEF)==功能。
对于任意值,从$开始:
public static Verbosity findByAbbr(String abbr){
for(Verbosity v:values()){
if(v.abbr()。equals(abbr)) {
return v;
}
}
返回null;
}
如果您的Profiler告诉您,只能继续前往Map实现。 p>
我知道它正在迭代所有的值,但只有3个枚举值,它几乎不值得任何其他的努力,事实上,除非你有很多价值,我不会打扰一张地图会足够快。
I would like to lookup an enum from its string value (or possibly any other value). I've tried the following code but it doesn't allow static in initialisers. Is there a simple way?
public enum Verbosity {
BRIEF, NORMAL, FULL;
private static Map<String, Verbosity> stringMap = new HashMap<String, Verbosity>();
private Verbosity() {
stringMap.put(this.toString(), this);
}
public static Verbosity getVerbosity(String key) {
return stringMap.get(key);
}
};
解决方案 Use the valueOf
method which is automatically created for each Enum.
Verbosity.valueOf("BRIEF") == Verbosity.BRIEF
For arbitrary values start with:
public static Verbosity findByAbbr(String abbr){
for(Verbosity v : values()){
if( v.abbr().equals(abbr)){
return v;
}
}
return null;
}
Only move on later to Map implementation if your profiler tells you to.
I know it's iterating over all the values, but with only 3 enum values it's hardly worth any other effort, in fact unless you have a lot of values I wouldn't bother with a Map it'll be fast enough.
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