Hello Riccardo,
It should be possible to support EnumSet with ExtendedType.
I did some prototyping, and it looks like you need to implement these parts:
1. an ExtendedTypeFactory as EnumSet has internal subclasses (that also
prevents using ValueType for this):
public ExtendedType getType(Class<?> objectClass) {
if(EnumSet.class.isAssignableFrom(objectClass)) {
return new EnumSetType();
}
return null;
}
2. an ExtendedType should deal with the serialization to/from the actual
datatype you are using in the DB:
public class EnumSetType implements ExtendedType<EnumSet> {
@Override
public void setJdbcObject(PreparedStatement statement, EnumSet value, int
pos, int type, int scale) throws Exception {
statement.setString(pos, toString(value));
}
@Override
public EnumSet<?> materializeObject(ResultSet rs, int index, int type)
throws Exception {
return fromString(rs.getString(index));
}
String toString(EnumSet value) {
// probably should account for the Enum type
}
EnumSet fromString(String value) {
}
}
3. and finally register factory with the runtime:
ServerModule.contributeTypeFactories(binder)
.add(new EnumSetFactory())
Hope this helps!
On Sat, Apr 5, 2025 at 8:03 PM Riccardo De Menna <[email protected]> wrote:
> Hello,
>
> I was wondering if there is a way to add a custom data type for a non
> extendable class. Specifically I’m thinking of java.util.EnumSet.
>
> I often use Enums in my object classes and I occasionally employ EnumSets
> when the case requires it. Unfortunately EnumSet is non extendable so I
> can’t define a subclass and then use that as java type in the modeller.
>
> Is there a way to hack the runtime into returning an EnumSet using a
> custom ValueType or ExtenedType for multiple attributes (it does work if
> there’s only one attribute using EnumSet but as soon as you define two the
> runtime gets confused).
>
> At the moment I’m just extending a HashSet<E extends Enum<E>> as a
> workaround but every time I see that I feel guilty not being able to use
> the ‘proper’ set collection for enums.
>
> Thank you,
> Riccardo De Menna
--
Best regards,
Nikita Timofeev
