Mailing-List: contact dev-help@openjpa.apache.org; run by ezmlm
Precedence: bulk
Reply-To: dev@openjpa.apache.org
Received-SPF: pass (athena.apache.org: domain of kwsutter@gmail.com designates
 64.233.166.182 as permitted sender)
DomainKey-Signature: a=rsa-sha1; c=nofws;
        d=gmail.com; s=gamma;
        h=message-id:date:from:to:subject:in-reply-to:mime-version:content-type:references;
        b=EhxuQnqlWeXKzyQAm3oIpP6hMeeGMqDpSLe+lYz1vN4HMcQhOCBzF0yWhoacCk+6IeiFrEOFG7SDMfNf6u1uCAH5RncLGljkhbO2xx/z7eyEJ30BSOHJACuJcacgDBll0LM/GxwLF1CL6O7CGkrCpovYIJwulUqia13sNVOiYKk=
Message-ID: <89c0c52c0804301157u55ae1a3t5a12d34db0b895d8@mail.gmail.com>
Date: Wed, 30 Apr 2008 13:57:33 -0500
From: "Kevin Sutter" <kwsutter@gmail.com>
To: dev@openjpa.apache.org
Subject: Re: UUIDs
In-Reply-To: <d4e11e980804300749i28130a5p7f18eb06efe16abf@mail.gmail.com>
MIME-Version: 1.0
Content-Type: multipart/alternative;
	boundary="----=_Part_2389_5247450.1209581853148"
References: <d4e11e980804281420v3d2f6497le133909d9b40cc50@mail.gmail.com>
	 <d4e11e980804300749i28130a5p7f18eb06efe16abf@mail.gmail.com>

------=_Part_2389_5247450.1209581853148
Content-Type: text/plain; charset=ISO-8859-1
Content-Transfer-Encoding: 7bit
Content-Disposition: inline

:-)  Quiet doesn't mean we're not busy...  :-)

My first thought when I read your append is why are you not just using the
built-in UUID generator that OpenJPA provides?  OpenJPA allows you to use a
generator on non-id fields.  We can either generate the UUID as a 16
character string or a 32 character hex value.  Would this usage suffice for
you, or do you have some other requirements for the use of the externalizer?

Here's a link to the documentation on the UUID generator:
http://openjpa.apache.org/docs/latest/manual/manual.html#jpa_overview_meta_gen

Kevin

On Wed, Apr 30, 2008 at 9:49 AM, Nikolas Everett <nik9000@gmail.com> wrote:

> I tried the attached message on the users list but didn't get any
> response.
> Will someone on the dev listserve help?  I'm researching an ORM solution
> for
> our company, and can't in good conscience pick one with quiet listservs.
> Thanks,
>
> --Nik
>
> ---------- Forwarded message ----------
> From: Nikolas Everett <nik9000@gmail.com>
> Date: Mon, Apr 28, 2008 at 5:20 PM
> Subject: UUIDs
> To: users@openjpa.apache.org
>
>
> I tried to search the archives and didn't find anything on this.  I'm
> using
> openjpa 1.0.2 and having problems with UUIDs backed into postgres 8.2.
>
> I have a class like:
> @Entity
> @Table(uniqueConstraints={@UniqueConstraint(columnNames="uuid")})
> public class Account {
>    @Id
>    @GeneratedValue(strategy=GenerationType.IDENTITY)
>    private int id;
>
>    @Persistent
>    @Column(nullable=false)
>    @Externalizer("java.util.UUID.toString")
>    @Factory("java.util.UUID.fromString")
>    @ElementType(UUID.class)
>    private UUID uuid;
>
> ...getters and setters...
> }
>
> The uuid column is created as a character varying 255, which is fine for
> now.
>
> I  have a method like this:
>    protected Account getAccountByUuid(UUID uuid) {
>        Query findAccount = this.em.createQuery("SELECT a FROM Account a
> WHERE a.uuid = ?1");
>        findAccount.setParameter(1, uuid);
>        try {
>            return (Account) findAccount.getSingleResult();
>        } catch (NoResultException e) {
>            Account account = new Account();
>            account.setUuid(uuid);
>            this.em.persist(account);
>            return account;
>        }
>    }
>
> Which throws an exception like this:
> Exception in thread "main" <openjpa-1.0.2-r420667:627158 nonfatal user
> error> org.apache.openjpa.persistence.ArgumentException: The parameter "0"
> is of type "java.util.UUID", but the declaration in the query is for type
> "java.lang.String".
>    at
>
> org.apache.openjpa.persistence.QueryImpl.validateParameter(QueryImpl.java:270)
>    at
>
> org.apache.openjpa.persistence.QueryImpl.validateParameters(QueryImpl.java:250)
>    at org.apache.openjpa.persistence.QueryImpl.execute(QueryImpl.java:231)
>    at
>
> org.apache.openjpa.persistence.QueryImpl.getSingleResult(QueryImpl.java:300)
>    at com.companyname.Classname.getAccountByUuid(FetchData.java:73)
>
> This isn't the behavior documented here:
>
> http://openjpa.apache.org/docs/latest/manual/ref_guide_pc_scos.html#d0e21916
>
> What can I do?
>
> Thanks in advance,
>
> --Nik
>

------=_Part_2389_5247450.1209581853148--