fuse 7.0 JPA persistence.xml schema is waiting for namespace handlers - jbossfuse

Question

I've tried all namespace handlers which are in JPA 2.1 registry persistence_1_0.xsd,persistence_2_0.xsd,persistence_2_1.xsd. As a result, none of them worked and thrown below error.
2.0,2.1
is waiting for namespace handlers [http://xmlns.jcp.org/xml/ns/persistence]
1.0
is waiting for namespace handlers [http://java.sun.com/xml/ns/persistence]
Let me know the cause of the issue.
Many Thanks In Advance.

Answer 1

If you check:
karaf#root()> feature:info jpa
Feature jpa 2.7.2
Description:
OSGi Persistence Container
Details:
JPA implementation provided by Apache Aries JPA 2.x. NB: this feature doesn't provide the JPA engine, you have to install one by yourself (OpenJPA for instance)
Feature has no configuration
Feature has no configuration files
Feature has no dependencies.
Feature contains followed bundles:
mvn:org.apache.aries.jpa.javax.persistence/javax.persistence_2.1/2.7.2
mvn:org.apache.geronimo.specs/geronimo-jta_1.1_spec/1.1.1.redhat-2 (overriden from mvn:org.apache.geronimo.specs/geronimo-jta_1.1_spec/1.1.1)
mvn:org.osgi/org.osgi.service.jdbc/1.0.0
mvn:org.apache.felix/org.apache.felix.coordinator/1.0.2 start-level=30
mvn:org.apache.aries.jpa/org.apache.aries.jpa.api/2.7.2 start-level=30
mvn:org.apache.aries.jpa/org.apache.aries.jpa.container/2.7.2 start-level=30
mvn:org.apache.aries.jpa/org.apache.aries.jpa.support/2.7.2 start-level=30
Feature contains followed conditionals:
Conditional(aries-blueprint) has no configuration
Conditional(aries-blueprint) has no configuration files
Conditional(aries-blueprint) has no dependencies.
Conditional(aries-blueprint) contains followed bundles:
mvn:org.apache.aries.jpa/org.apache.aries.jpa.blueprint/2.7.2 start-level=30
You'll see NB: this feature doesn't provide the JPA engine, you have to install one by yourself (OpenJPA for instance). This description seems old. You need actual JPA provider, like:
karaf#root()> feature:info hibernate
Feature hibernate 5.3.10.Final-redhat-00001
Description:
Hibernate JPA engine support
Feature has no configuration
Feature has no configuration files
Feature depends on:
wrap 0.0.0
hibernate-orm 5.3.10.Final-redhat-00001
Feature contains followed bundles:
mvn:net.bytebuddy/byte-buddy/1.9.5.redhat-00001 (overriden from mvn:net.bytebuddy/byte-buddy/1.9.5.redhat-00001)
Feature has no conditionals.
(versions of bundles from Fuse newer than 7.0).
So please install additionally hibernate feature:
karaf#root()> feature:install hibernate
karaf#root()> la -l|grep hibernate
249 │ Active │ 80 │ 5.0.4.Final-redhat-00001 │ mvn:org.hibernate.common/hibernate-commons-annotations/5.0.4.Final-redhat-00001
250 │ Active │ 80 │ 5.3.10.Final-redhat-00001 │ mvn:org.hibernate/hibernate-core/5.3.10.Final-redhat-00001
251 │ Active │ 80 │ 5.3.10.Final-redhat-00001 │ mvn:org.hibernate/hibernate-osgi/5.3.10.Final-redhat-00001
EDIT 2019-11-07:
I checked (upcoming Fuse 7.5, but should be valid for 7.0) and found the problem you have.
If you check:
karaf#root()> ls PersistenceProvider
[javax.persistence.spi.PersistenceProvider]
-------------------------------------------
javax.persistence.provider = org.hibernate.jpa.HibernatePersistenceProvider
service.bundleid = 250
service.id = 468
service.scope = bundle
Provided by :
hibernate-osgi (250)
Used by:
Apache Aries JPA Specification 2.1 API (244)
Camel Content-Based Router Example [EXAM-PREP] (256)
you'll see there's org.hibernate.jpa.HibernatePersistenceProvider JPA provider registered by Hibernate.
You've however added (in META-INF/persistence.xml):
<provider>org.hibernate.ejb.HibernatePersistence</provider>
You should either remove this provider or use org.hibernate.jpa.HibernatePersistenceProvider because it affects an OSGi filter created by org.apache.aries.jpa.container.impl.PersistenceProviderTracker#createFilter for your bundle. So that's the reason why you didn't have EMF registered.
With this change, I found it works:
karaf#root()> ls EntityManagerFactory
[javax.persistence.EntityManagerFactory]
----------------------------------------
hibernate.connection.pool_size = 25
hibernate.dialect = org.hibernate.dialect.DerbyDialect
hibernate.hbm2ddl.auto = create
hibernate.show_sql = true
javax.persistence.jdbc.driver = org.apache.derby.jdbc.EmbeddedDriver
javax.persistence.jdbc.url = jdbc:derby:memory:order;create=true
javax.persistence.jdbc.user = sa
osgi.unit.name = camel
osgi.unit.provider = org.hibernate.jpa.HibernatePersistenceProvider
osgi.unit.version = 4.1.4
service.bundleid = 256
service.id = 501
service.scope = singleton
Provided by :
Camel Content-Based Router Example [EXAM-PREP] (256)
Used by:
Camel Content-Based Router Example [EXAM-PREP] (256)