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javaenumsenumset

Elegant way to deserialise EnumSet from String

I'd like to serialise some EnumSet<FooType> to String using its toString() method.

E.g.: EnumSet.of(FooType.COMMON, FooType.MEDIUM).toString() will give [COMMON, MEDIUM].

The question is about an elegant way to deserialise such a string back to the EnumSet<FooSet>. I'm looking for some commonly known library (may be like apache-commons) or a standard Util-class for such things.

Something like: EnumSetUtil.valueOf(FooType.class, "[COMMON, MEDIUM]")

I've implemented this thing in such way:

public static <E extends Enum<E>> EnumSet<E> valueOf(Class<E> eClass, String str) {
    String[] arr = str.substring(1, str.length() - 1).split(",");
    EnumSet<E> set = EnumSet.noneOf(eClass);
    for (String e : arr) set.add(E.valueOf(eClass, e.trim()));
    return set;
}

But, may be there is a ready solution, or a dramatically easy way for doing this.

Solution

  • With Java 8 you can do something like this with Lambda expressions and streams:

    EnumSet.copyOf(Arrays.asList(str.split(","))
.stream().map(FooType::valueOf).collect(Collectors.toList()))