Bar.java

class Scratch {
    public static void main(String[] args) {
        Bar defined = Bar.of("1");
        Bar unknown = Bar.of("unknown");

        assert defined.getValue().equals("1");
        assert unknown.getValue().equals("unknown");

    }
}

interface Bar {
    String getValue();

    static Bar of(String value) {
        try {
            return DefinedBar.valueOf(value);
        } catch (Exception e) {
            return new UnknownBar(value);
        }
    }
}

enum DefinedBar implements Bar {
    OPTION1("1"), OPTION2("2"), OPTION3("3");
    private final String value;

    DefinedBar(String value) {
        this.value = value;
    }

    public String getValue() {
        return value;
    }
}

final class UnknownBar implements Bar {
    private final String value;

    UnknownBar(String value) {
        this.value = value;
    }

    public String getValue() {
        return value;
    }
}