Just to document more thoughts and findings.
1) I was using the wrong annotation, I should have been using
@PersistentCollection
2) this seems to be a more wide spread problem with defining
attributes to collections, i.e.
- collection of enums needs to have @Enumerated configurations
- collection of Dates needs to have @Temporal configurations
- even collection of Strings seems to be missing a
@Column(nullable=false, length=32) style annotation.
I think the problem is much bigger and wide spread than I originaly though,
I don't think I'll be able to sort out a patch.
On Sun, Mar 29, 2009 at 07:55:06AM -0700, Tedman Leung wrote:
> yes I know I can do manual hacks to get them stored the way I want to, but
> I was asking if there was a jpa / openjpa annotation to allow that.
>
> As an example, I can just use @Enumerated on a single enum, so it seems
> logical that some one would have thought about storing a collection of
> enums.
>
> As for why I want them as strings instead of ordinals - the usual reasons,
> i.e. it's safer for changes as the ordering won't accidentally corrupt my
> data (and without telling me), and it's easier to look into the database
> via sql or something and just know what's going on / get simple reports
> etc.
>
> I'm guessing right now that it's not possible at all and that no one has
> done anything towards this. I might have to rummage through the source
> and try to see if I can figure out how it works and hack a patch to
> submit. It seemed like a very straight forward use case though so I'm
> surprised no one has asked or done anything about this before.
>
>
>
> On Sat, Mar 28, 2009 at 10:13:16PM -0700, Paul Copeland wrote:
> > What is your objective? Do you want some non-JPA application to see
> > them in the database as Strings?
> >
> > At some point you have add these Enums to the collection one at a time.
> > You can use an addEnum() method or an Entity listener to convert them to
> > Strings at that point one at a time. And a subclass of the Collection
> > type to getEnum() from the Collection when you fetch them back.
> >
> > new MyStringEnumHashSet<MyStringEnumType>()
> >
> > On 3/28/2009 9:27 PM, Tedman Leung wrote:
> >> No, I'm talking about when the enum is in a collection.
> >>
> >> i.e.
> >>
> >> Private HashSet<Gender> genders=new HashSet<Gender>();
> >>
> >> So no, either the @Enumerated helps, nor does calling name() or
> >> toString as neither are possible.
> >>
> >> I'm storing a Collection of enums , not a single Enum.
> >>
> >> There seems to be no examples of this nor any documentation about the
> >> ability to do this that I can find. The default seems to use the
> >> ordinal value both for table generation and storage value.
> >>
> >>
> >>
> >>
> >> On Sat, Mar 28, 2009 at 01:56:13PM -0700, Paul Copeland wrote:
> >>
> >>> Hi - This is from the OpenJPA relations example -
> >>>
> >>> @Basic @Enumerated(EnumType.STRING)
> >>> private Gender gender;
> >>>
> >>> public static enum Gender { MALE, FEMALE }
> >>>
> >>> public void setGender(Gender gender) {
> >>> this.gender = gender;
> >>> }
> >>>
> >>> See section 12.8.1.2 in the OpenJPA Overview
> >>>
> >>> - Paul
> >>>
> >>> On 3/28/2009 1:33 PM, catalina wei wrote:
> >>>
> >>>> Ted,
> >>>> If you are using Java 5, then you could use name() or toString() API on
> >>>> the
> >>>> Enum to get the name of the enum constant in String value.
> >>>>
> >>>> Catalina
> >>>>
> >>>> On Wed, Mar 25, 2009 at 9:48 AM, Tedman Leung <ted...@sfu.ca> wrote:
> >>>>
> >>>>
> >>>>> Anyone know how to store a collection of enums as Strings instead of
> >>>>> their
> >>>>> ordinal values? (preferably with annotations...)
> >>>>>
> >>>>> i.e.
> >>>>> @ManyToMany
> >>>>> private Set<MyEnum> myEnums=new HashSet<MyEnum>();
> >>>>>
> >>>>>
> >>>>> --
> >>>>> Ted Leung
> >>>>> ted...@sfu.ca
> >>>>>
> >>>>> It's time for a new bike when the bulb in your shift light burns out.
> >>>>>
> >>>>>
> >>>>
> >>
> >>
> >
>
> --
> Ted Leung
> ted...@sfu.ca
>
> The most important words I've learned to say - "I don't know".
--
Ted Leung
ted...@sfu.ca
It is easier to speak wisely than to act wisely.
