How to cast a String value to an Enum value by Class?

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Lookup Java enum by string value 23 answers

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It's actually kind of a pain because of the way Enum is declared. You wouldn't be able to call valueOf with a Class<?> (nor eg a Class<? extends Enum<?>> ). The only way to do it without unchecked casting is to go through getEnumConstants :

public boolean tryCast(String value){
    for(Object o : enumClass.getEnumConstants()) {
        Enum<?> e = (Enum<?>) o;
        if(e.name().equals(value))
            return true;
    }
    return false;
}

If you don't care about the unchecked cast you can do:

try {
    Enum.valueOf( (Class) enumClass, value );
    return true;
} catch(IllegalArgumentException e) {
    return false;
}

But, you know, some people will grumble because it's a raw type. getEnumConstants is probably better anyways since then you don't use exceptions for this kind of thing.

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In addition, since you have a Class<?> you might want to perform a check like

if( !Enum.class.isAssignableFrom(enumClass) )
    return false;

or throw an exception in the constructor.

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