Hi Kevan,
many thanks a lot for the detailed explanation.
I have added the persistence schemas to our Aries JPA container
project, closely following the OpenJPA example.
Valentin
On 2 Feb 2010, at 02:05, Kevan Miller wrote:
On Feb 1, 2010, at 11:59 AM, Valentin Mahrwald wrote:
Hi,
currently we require the persistence schema to be located somewhere
on the web (like http://java.sun.com/xml/ns/persistence/persistence_1_0.xsd
. This approach has a couple of issues
- the JPA container must be able to access the network
- the first time we load the schema we incur a speed penalty
- the JPA2 schema isn't yet available in the canonical
java.sun.com/... location.
Now, I have noticed that OpenJPA ships a copy of the
persistence.xsd in its binaries. The file is located under org/
apache/openjpa/persistence/persistence.xsd.rsrc.
Could we potentially do the same in the Aries JPA container? And
what license issues are there to be aware of?
Sure. As you've no doubt noticed persistence.xsd is dual licensed --
GPL and CDDL. For dual-licensed materials, you must choose a license
and note the choice in the NOTICE file.
CDDL has been classified as a "weak copyleft" license by the ASF --
http://www.apache.org/legal/resolved.html#category-b
Note that in general, "weak copyleft" licensed binaries are
acceptable for an Apache project, but "weak copyleft" licensed
source is not acceptable. There's an importance exception to this
and fits the use case for persistence.xml -- source that is
unmodified and unlikely to be changed (i.e. when it defines a
"standard") may be included in an Apache release.
With minor quibbles, I'd say that the OpenJPA LICENSE/NOTICE files
are good example of how to handle:
https://svn.apache.org/repos/asf/openjpa/tags/2.0.0-beta/LICENSE.txt
https://svn.apache.org/repos/asf/openjpa/tags/2.0.0-beta/NOTICE.txt
--kevan
