openjpa-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Patrick Linskey" <plins...@bea.com>
Subject RE: Using query hints for mapping extensions in orm.xml
Date Wed, 24 Jan 2007 17:16:30 GMT
Firstly, thanks for putting this together.

I don't think that portability is a huge problem. I agree with the three
scenarios that Albert mentioned, but I think that we can refine #1:

> 1) if an application wants to be fully portable between providers, the
> standard orm.xsd must be specified. This will inhibit the use 
> of openjpa
> features.

I would revise this as follows:

1) if an application wants to be fully portable between providers, the
standard orm.xsd must be specified. This will inhibit the use of OpenJPA
features in that file, so a parallel openjpa-orm.xml file must be used
which conforms to the OpenJPA XSD and adds the additional information.

We could even create a second XSD for that situation that allows only
OpenJPA content to help prevent people from putting conflicting stanzas
in the two files.

-Patrick

-- 
Patrick Linskey
BEA Systems, Inc. 

_______________________________________________________________________
Notice:  This email message, together with any attachments, may contain
information  of  BEA Systems,  Inc.,  its subsidiaries  and  affiliated
entities,  that may be confidential,  proprietary,  copyrighted  and/or
legally privileged, and is intended solely for the use of the individual
or entity named in this message. If you are not the intended recipient,
and have received this message in error, please immediately return this
by email and then delete it. 

> -----Original Message-----
> From: Albert Lee [mailto:allee8285@gmail.com] 
> Sent: Wednesday, January 24, 2007 8:38 AM
> To: open-jpa-dev@incubator.apache.org
> Subject: Re: Using query hints for mapping extensions in orm.xml
> 
> First, I would not expected other providers will handle the special
> openjpa.orm.xsd even if it is spec'ed out in the document 
> header. If they
> choose to ignore the new schema and proceed to parse the 
> document content
> using the standard orm.xsd, then any openjpa specific stanza 
> will probably
> be flagged as non-compliance.
> 
> The other scenario is: what about if the document does not specify the
> schema at all, like the original sample. I suspect most providers will
> tolerate this scenario, just like openjpa does.
> 
> Can the solutions be:
> 1) if an application wants to be fully portable between providers, the
> standard orm.xsd must be specified. This will inhibit the use 
> of openjpa
> features.
> 2) if an application wants to use openjpa specific stanza and 
> still be used
> by other provider, don't specify the schema at all in the 
> document. Hoping
> the other providers will tolerate and ignore the openjpa features.
> 3) if an application wants to be openjpa schema compliance, then use
> openjpa.orm.xsd in the document header and openjpa can validate the
> document. However this will prevent the application to be 
> portable to other
> providers.
> 
> Albert Lee.
> 
> 
> On 1/24/07, Kevin Sutter <kwsutter@gmail.com> wrote:
> >
> > Thank you, Albert, for your experimentation.  The updated schema
> > definition
> > (openjpa_orm_1_0.xsd) and the example openjpa_orm.xml seems 
> to be what we
> > are looking for.  I guess the only concern is whether we 
> can count on
> > other
> > JPA implementations to ignore this extra schema definition 
> and just rely
> > on
> > the standard orm.xsd.
> >
> > Question:  Even if other JPA providers are smart enough to 
> ignore our
> > specialized schema and use the standard JPA schema, what 
> happens to our
> > extension elements?  Do they get ignored as well?  Or, will the
> > verification
> > step still trip over these new/updated elements?
> >
> > Thanks again,
> > Kevin
> >
> >
> > On 1/23/07, Albert Lee <allee8285@gmail.com> wrote:
> > >
> > > Somehow the one of the attachment (openjpa_orm_1_0.xsd) 
> from my previous
> > > note did not make it to this forum.
> > >
> > > Try again here.
> > >
> > 
> --------------------------------------------------------------
> --------------------------------
> > >
> > > <?xml version="1.0" encoding="UTF-8"?>
> > > <!--
> > >     OpenJPA specific orm.xml schema locates in: (E.g.)
> > >
> > >
> > 
> http://incubator.apache.org/openjpa/xml/ns/persistence/openjpa
> _orm_1_0.xsd
> > > "
> > >
> > >     This schema extends
> > http://java.sun.com/xml/ns/persistence/orm_1_0.xsd
> > > with
> > >         OpenJPA specific stanza and uses the same name space as
> > >             "http://java.sun.com/xml/ns/persistence/orm"
> > > -->
> > > <xsd:schema
> > >                  version="1.0"
> > >                xmlns:xsd="http://www.w3.org/2001/XMLSchema"
> > >          targetNamespace=" 
> http://java.sun.com/xml/ns/persistence/orm"
> > >                
> xmlns:orm="http://java.sun.com/xml/ns/persistence/orm"
> > >       elementFormDefault="qualified"
> > >     attributeFormDefault="unqualified"
> > >   >
> > >
> > >   <xsd:annotation>
> > >     <xsd:documentation>
> > >       @(#)openjpa_orm_1_0.xsd 1.0  Jan 22 2007
> > >     </xsd:documentation>
> > >   </xsd:annotation>
> > >   <xsd:annotation>
> > >      <xsd:documentation><![CDATA[
> > >
> > >        This is the XML Schema for extending the persistence
> > > object-relational
> > >        mapping file for OpenJPA specific features.
> > >
> > >        The file may be named "META-INF/orm.xml" in the persistence
> > >        archive or it may be named some other name which would be
> > >        used to locate the file as resource on the classpath.
> > >
> > >      ]]></xsd:documentation>
> > >   </xsd:annotation>
> > >
> > >   <!-- Redefine the orm_1_0.xsd with additional OpenJPA 
> extensions -->
> > >   <xsd:redefine schemaLocation="
> > http://java.sun.com/xml/ns/persistence/orm_1_0.xsd
> > > ">
> > >
> > >     <!--
> > >         Append optional single <data-cache> element to <entity>.
> > >           Valid values are "true" | "false" | "1" | "0".
> > >           Default value is "false".
> > >     -->
> > >     <xsd:complexType name="entity">
> > >       <xsd:complexContent>
> > >         <xsd:extension base="orm:entity">
> > >           <xsd:sequence>
> > >             <xsd:element name="data-cache" type="xsd:boolean"
> > > minOccurs="0" maxOccurs="1" default="false"/>
> > >           </xsd:sequence>
> > >         </xsd:extension>
> > >       </xsd:complexContent>
> > >     </xsd:complexType>
> > >
> > >
> > >     <!--
> > >         Append optional single <jdbc-nonpolymorphic> element to
> > > <one-to-many>.
> > >           Valid values are "true" | "false" | "1" | "0".
> > >           Default value is "false".
> > >
> > >         Append optional single <jdbc-eager-fetch-mode> element to
> > > <one-to-many>.
> > >           Valid values are "parallel" | "others".
> > >           Default value is "parallel".
> > >     -->
> > >     <xsd:complexType name="one-to-many">
> > >       <xsd:complexContent>
> > >         <xsd:extension base="orm:one-to-many">
> > >           <xsd:sequence>
> > >
> > >             <xsd:element name="jdbc-nonpolymorphic" 
> type="xsd:boolean"
> > > minOccurs="0" maxOccurs="1" default="false"/>
> > >
> > >             <xsd:element name="jdbc-eager-fetch-mode" 
> minOccurs="0"
> > > maxOccurs="1" default="parallel">
> > >               <xsd:simpleType>
> > >                 <xsd:restriction base="xsd:string">
> > >                   <xsd:enumeration value="parallel"/>
> > >                   <xsd:enumeration value="others"/>
> > >                 </xsd:restriction>
> > >               </xsd:simpleType>
> > >             </xsd:element>
> > >
> > >           </xsd:sequence>
> > >         </xsd:extension>
> > >       </xsd:complexContent>
> > >     </xsd:complexType>
> > >
> > >   </xsd:redefine>
> > >
> > > </xsd:schema>
> > >
> > >
> > > Albert Lee
> > >
> >
> >
> 

Mime
View raw message