I would like to fill a list with all possible values of an enum

Since I recently fell in love with EnumSet, I leveraged allOf()

我想用一个枚举的所有可能值填充一个列表，因为我最近爱上了EnumSet，我利用Allof()

EnumSet<Something> all = EnumSet.allOf( Something.class);
List<Something> list = new ArrayList<>( all.size());
for (Something s : all) {
    list.add( s);
}
return list;

Is there a better way (as in non obfuscated one liner) to achieve the same result?

有没有更好的方法(就像在非模糊处理的情况下)来达到同样的效果？

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I wouldn't use a List in the first places as an EnumSet is more approriate but you can do

首先，我不会使用列表，因为EnumSet更合适，但您可以这样做

List<Something> somethingList = Arrays.asList(Something.values());

or

或

List<Something> somethingList =
                 new ArrayList<Something>(EnumSet.allOf(Something.class));

Class.getEnumConstants()

Class.getEnumConstants()

List<SOME_ENUM> enumList = Arrays.asList(SOME_ENUM.class.getEnumConstants());

There is a constructor for ArrayList which is

ArrayList有一个构造函数，它是

ArrayList(Collection<? extends E> c) 

Now, EnumSet extends AbstractCollection so you can just do

现在，EnumSet扩展了AbstractCollection，因此您可以只做

ArrayList<Something> all = new ArrayList<Something>(enumSet)

try

试试看

enum E {
    E1, E2, E3
}

public static void main(String[] args) throws Exception {
    List<E> list = Arrays.asList(E.values());
    System.out.println(list);
}

List<Something> result = new ArrayList<Something>(all);

EnumSet is a Java Collection, as it implements the Set interface:

EnumSet是一个Java集合，因为它实现了Set接口：

public interface Set<E> extends Collection<E> 

So anything you can do with a Collection you can do with an EnumSet.

因此，您可以使用Collection执行的任何操作都可以使用EnumSet执行。

This is a bit more readable:

下面的代码更具可读性：

Object[] allValues = all.getDeclaringClass().getEnumConstants();

Try this:

试试这个：

... = new ArrayList<Something>(EnumSet.allOf(Something.class));

as ArrayList has a constructor with Collection<? extends E>. But use this method only if you really want to use EnumSet.

因为ArrayList有一个集合<？扩展E>。但只有当您真的想要使用EnumSet时才使用此方法。

All enums have access to the method values(). It returns an array of all enum values:

所有枚举都可以访问方法值()。它返回一个包含所有枚举值的数组：

... = Arrays.asList(Something.values());

You can use also:

您还可以使用：

Collections.singletonList(Something.values())

I know the question is asking about List but I think I have possible cleaner solutions as well as one solution using List that wasn't added yet.

我知道问题是关于List的，但我想我有可能更干净的解决方案，以及一个使用List的解决方案，但还没有添加。

I'm using Java 17

我使用的是Java 17

Simply use a array of enum

public class Main {
    static public enum Something {
        One,
        Two,
        Three,
        Four,
        Five,
        ;

    }

    public static void main(String[] args) {
        Something[] somethings = Something.values();
        for (Something something: somethings) {
            System.out.printf("- %s\n", something);
        }

    }

}

Simple get all values of the enum with enum.values()

简单地用enum.values（）获取枚举的所有值

Something[] somethings = Something.values();

Something[]Something=Something.Values()；

Use list.of

import java.util.List;

public class Main {
    static public enum Something {
        One,
        Two,
        Three,
        Four,
        Five,
        ;

    }

    public static void main(String[] args) { 
        List<Something> somethings2 = List.of(Something.values());
        for (Something something: somethings2) {
            System.out.printf("- %s\n", something);
        }
    }

}

I've seen solutions using Arrays.asList( which as described in What is the difference between List.of and Arrays.asList?

我见过使用Arrays.asList的解决方案(如List.of和Arrays.asList之间的区别所述？

Arrays.asList returns a mutable list while the list returned by List.of is immutable

or

或

Arrays.asList allows null elements while List.of doesn't

And few other reasons.
Because theoretically, from an Array of enum you should't be able to mutate it (adding / removing elements) I think it makes more sense to use List.of
Anyways, it depends by use cases and both ways are probably valid

几乎没有其他原因。因为从理论上讲，您不应该能够从枚举数组中改变它(添加/删除元素)。我认为使用List.of Anyway更有意义，这取决于用例，两种方法都可能是有效的

private ComboBox gender;
private enum Selgender{Male,Famle};
ObservableList<Object> observableList  =FXCollections.observableArrayList(Selgender.values());